Document and Entity Information	3 Months Ended
Document and Entity Information	Jun. 30, 2013	Aug. 01, 2013
Document Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2013
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q1
Entity Registrant Name	AMERICAN SUPERCONDUCTOR CORP /DE/
Entity Central Index Key	0000880807
Current Fiscal Year End Date	--03-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		63,124,801

Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Current assets:
Cash and cash equivalents	$ 32,608	$ 39,243
Accounts receivable, net	11,088	18,864
Inventory	30,752	33,473
Prepaid expenses and other current assets	23,868	22,469
Restricted cash	824	6,136
Total current assets	99,140	120,185
Property, plant and equipment, net	71,931	74,626
Intangibles, net	2,536	2,749
Restricted cash	6,098	4,820
Deferred tax assets	5,421	5,354
Other assets	9,067	9,020
Total assets	194,193	216,754
Current liabilities:
Accounts payable and accrued expenses	25,481	30,138
Note payable, current portion, net of discount of $363 as of June 30, 2013 and $458 as of March 31, 2013	4,252	4,158
Convertible note, current portion, net of discount of $3,259 as of June 30, 2013 and $4,289 as of March 31, 2013	7,426	4,610
Derivative liability	3,693	4,162
Adverse purchase commitments	1,179	1,440
Deferred revenue	20,031	29,805
Deferred tax liabilities	5,452	5,444
Total current liabilities	67,514	79,757
Note Payable, net of discount of $39 as of June 30, 2013 and $95 as of March 31, 2013	2,268	3,367
Convertible note net of discount of $172 as of June 30, 2013 and $600 as of March 31, 2013	3,532	5,881
Deferred revenue	1,234	1,340
Other liabilities	1,165	1,291
Total liabilities	75,713	91,636
Commitments and contingencies (Note 12)
Stockholders' equity:
Common stock	610	603
Additional paid-in capital	927,807	923,847
Treasury stock	(370)	(313)
Accumulated other comprehensive income	1,077	1,112
Accumulated deficit	(810,644)	(800,131)
Total stockholders' equity	118,480	125,118
Total liabilities and stockholders' equity	$ 194,193	$ 216,754

Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Statement Of Financial Position [Abstract]
Note payable, current portion, net of discount	$ 363	$ 458
Current portion of convertible note, net of discount	3,259	4,289
Note payable, net of current portion and discount	39	95
Convertible note net of current portion and discount	$ 172	$ 600

Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Income Statement [Abstract]
Revenues	$ 23,086	$ 28,716
Cost and operating expenses:
Cost of revenues	17,987	16,926
Research and development	3,027	3,910
Selling, general and administrative	10,827	13,799
Restructuring and impairments	13	128
Amortization of acquisition related intangibles	82	81
Total cost and operating expenses	31,936	34,844
Operating loss	(8,850)	(6,128)
Change in fair value of derivatives and warrants	469	(2,388)
Interest expense, net	(2,111)	(2,718)
Other income, net	69	123
Loss before income tax expense	(10,423)	(11,111)
Income tax expense (benefit)	90	(836)
Net loss	$ (10,513)	$ (10,275)
Net loss per common share
Basic	$ (0.18)	$ (0.20)
Diluted	$ (0.18)	$ (0.20)
Weighted average number of common shares outstanding
Basic	58,300	51,191
Diluted	58,300	51,191

Condensed Consolidated Statements of Comprehensive (Loss) Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (10,513)	$ (10,275)
Other comprehensive loss, net of tax:
Foreign currency translation losses	(35)	(1,168)
Unrealized gains on investments		4
Total other comprehensive loss, net of tax	(35)	(1,164)
Comprehensive loss	$ (10,548)	$ (11,439)

Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net loss	$ (10,513)	$ (10,275)
Adjustments to reconcile net (loss) income to net cash (used in) provided by operations:
Depreciation and amortization	2,655	3,344
Stock-based compensation expense	2,135	1,994
Restructuring charges, net of payments	(27)	(39)
Provision for excess and obsolete inventory	160	250
Adverse purchase commitment recoveries, net		(7,301)
Loss on minority interest investments	248	812
Change in fair value of derivatives and warrants	(469)	2,388
Non-cash interest expense	1,672	2,282
Other non-cash items	686	200
Changes in operating asset and liability accounts:
Accounts receivable	8,111	4,132
Inventory	2,861	136
Prepaid expenses and other current assets	(1,151)	848
Accounts payable and accrued expenses	(5,464)	(6,449)
Deferred revenue	(10,211)	(3,913)
Net cash used in operating activities	(9,307)	(11,591)
Cash flows from investing activities:
Purchase of property, plant and equipment	(97)	(88)
Proceeds from the maturity of marketable securities		100
Proceeds from the sale of property, plant and equipment	25
Change in restricted cash	4,051	(6,858)
Change in other assets	(205)
Net cash provided by (used in) investing activities	3,774	(6,846)
Cash flows from financing activities:
Employee taxes paid related to net settlement of equity awards	(57)	(36)
Proceeds from the issuance of debt, net of expenses		32,961
Repayment of debt	(1,154)
Net cash (used in) provided by financing activities	(1,211)	32,925
Effect of exchange rate changes on cash and cash equivalents	109	(280)
Net (decrease) increase in cash and cash equivalents	(6,635)	14,208
Cash and cash equivalents at beginning of period	39,243	46,279
Cash and cash equivalents at end of period	32,608	60,487
Supplemental schedule of cash flow information:
Cash paid for income taxes, net of refunds	145	(828)
Issuance of common stock to settle liabilities	1,832	1,016
Cash paid for interest	$ 216

Nature of the Business and Operations and Liquidity

3 Months Ended

Jun. 30, 2013

Accounting Policies [Abstract]

Nature of the Business and Operations and Liquidity

1.	Nature of the Business and Operations and Liquidity

Nature of the Business and Operations

American Superconductor Corporation (“AMSC” or the “Company”) was founded on April 9, 1987. The Company is a leading provider of megawatt-scale solutions that lower the cost of wind power and enhance the performance of the power grid. In the wind power market, the Company enables manufacturers to field wind turbines through its advanced engineering, support services and power electronics products. In the power grid market, the Company enables electric utilities and renewable energy project developers to connect, transmit and distribute power through its transmission planning services and power electronics and superconductor-based products. The Company’s wind and power grid products and services provide exceptional reliability, security, efficiency and affordability to its customers.

These unaudited condensed consolidated financial statements of the Company have been prepared on a going concern basis in accordance with United States generally accepted accounting principles (“GAAP”) and the Securities and Exchange Commission’s (“SEC”) instructions to Form 10-Q. The going concern basis of presentation assumes that the Company will continue operations and will be able to realize its assets and discharge its liabilities and commitments in the normal course of business. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been condensed or omitted pursuant to those instructions. The year-end condensed balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The unaudited condensed consolidated financial statements, in the opinion of management, reflect all adjustments (consisting of normal recurring adjustments) necessary for a fair statement of the results for the interim periods ended June 30, 2013 and 2012 and the financial position at June 30, 2013.

Liquidity

The Company has experienced recurring operating losses and as of June 30, 2013, the Company had an accumulated deficit of $810.6 million. In addition, the Company has experienced recurring negative operating cash flows, which has resulted in a decrease in its cash balance. These factors raise substantial doubt about the Company’s ability to continue as a going concern. These financial statements do not include any adjustments that might result from the outcome of this uncertainty. At June 30, 2013, the Company had cash and cash equivalents of $32.6 million. Cash used in operations for the three months ended June 30, 2013 was $9.3 million. The Company obtained financing totaling approximately $35.0 million during the quarter ended June 30, 2012. No additional financing has been obtained since then.

The Company is currently in the process of consolidating certain business operations to reduce facility costs. The Company expects that its cost reduction efforts and anticipated revenue growth will result in a reduction of cash used for operations during the fiscal year ending March 31, 2014, compared to the prior year. In July 2013, the Company reduced its workforce by approximately 7% and expects to record a restructuring charge for severance and other costs of approximately $1.0 million in the quarter ending September 30, 2013. The Company plans to closely monitor its expenses and if required, expects to further reduce operating costs and capital spending to enhance liquidity.

On April 4, 2012, the Company completed a private placement of $25.0 million aggregate principal amount of a 7% senior unsecured convertible note (the “Initial Note”). On June 5, 2012, the Company entered into a Loan and Security Agreement (the “Term Loan”), under which the Company borrowed $10.0 million. On December 20, 2012, the Company agreed to exchange the Initial Note for a new unsecured, senior convertible note (the “Exchanged Note”), which had the same principal amount and accrued interest as the Initial Note at the time of the exchange. See Note 10, “Debt”, for further information regarding these debt arrangements, including the covenants, restrictions and events of default under the agreements.

On June 5, 2012, the Company entered into a Loan and Security Agreement (as modified by that certain Limited Waiver dated June 11, 2013, the “Term Loan”), under which the Company borrowed $10.0 million. The Term Loan contains certain covenants and restrictions including, among others, a requirement to maintain a minimum unrestricted cash balance in the U.S. equal to the remaining principal balance. (See Note 10, “Debt”, for further information regarding these debt arrangements, including the covenants, restrictions and events of default under the agreements.) The Company believes that it is in compliance with the covenants and restrictions included in the agreements governing these debt arrangements as of the date of this Quarterly Report on Form 10-Q.

In order for the Company to continue operations beyond the next twelve months and be able to discharge its liabilities and commitments in the normal course of business, the Company needs to significantly increase sales through executing its strategy to broaden its customer base, enter new markets, and commercialize its superconductor product line. In addition, the Company may need to further reduce operating expenses in line with business conditions in order to decrease the amount of cash used in operations and continue to work with the holder of its convertible note in order to maintain the ability to make monthly amortization payments on the convertible note in shares of common stock. In July 2013, the holder of the Exchanged Note converted $4.0 million of the Exchanged Note into shares of common stock in accordance with the accelerated payment provisions of the Exchanged Note. In addition, the Company is actively seeking to sell its minority investments in Tres Amigas and Blade Dynamics and has recently engaged a financial advisor to assist with that effort. (See Note 13, “Equity Investments”, for further information about such investments.) There can be no assurance that we will be able to sell one or both of these investments on commercially reasonable terms or at all.

If the Company successfully executes on its plans discussed above, then the Company believes that its available cash, together with additional reductions in operating costs and capital expenditures that it expects to make, if necessary, will be sufficient to fund its operations, capital expenditures and scheduled cash payments under its debt obligations through June 30, 2014. The Company’s ability to pay required monthly installment payments under the Exchanged Note in equity instead of cash is based on certain stock price and trading volume conditions that are outside of the Company’s control. If one or both of these equity conditions are not met (absent a waiver from the lender), the Company may be required to make required monthly installment payments in cash. As of the date of this Form 10-Q, the Company has only made payments to the lender in shares of common stock and as a result, the principal balance has been reduced by $10.6 million through June 30, 2013. If the Company fails one or both of the equity conditions, the Company can still make required payments in its common stock with a waiver from the lender, which has been provided in the past. There is no assurance that the lender will provide any waivers in the future. The Company’s liquidity is highly dependent on its ability to profitably grow revenues through both the acquisition of new customers and growth from its existing customers, manage its operating expenses, continue to make amortization payments under the Exchanged Note in shares of the Company’s common stock, maintain compliance with the covenants and restrictions on its debt obligations (or obtain waivers from our lenders in the event of non-compliance), and raise additional capital, as required. Potential sources of additional capital include sales of its minority investments in Tres Amigas and Blade Dynamics, (see Note 13, “Equity Investments”, for further information about such investments) and obtaining additional financing (with the consent of our lenders, if required). There can be no assurance that sources of additional financing or other forms of liquidity will be available on commercially acceptable terms or at all.

The results of operations for an interim period are not necessarily indicative of the results of operations to be expected for the fiscal year. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the fiscal year ended March 31, 2013 (fiscal 2012) which are contained in the Company’s Annual Report on Form 10-K.

Stock-Based Compensation

3 Months Ended

Jun. 30, 2013

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

2.	Stock-Based Compensation

The Company accounts for its stock-based compensation at fair value. The following table summarizes stock-based compensation expense by financial statement line item for the three months ended June 30, 2013 and 2012 (in thousands):


	Three months ended June 30,
	2013		2012
Cost of revenues	$	205	$	170
Research and development		575		562
Selling, general and administrative		1,355		1,262

Total	$	2,135	$	1,994

During the three months ended June 30, 2013, the Company granted approximately 314,765 stock options and issued 154,080 shares of common stock in-lieu of cash bonuses to employees under the 2007 Stock Incentive Plan. The shares issued in-lieu of cash bonuses vest immediately, the options granted vest upon the passage of time, generally 3 years. For awards that vest upon the passage of time, expense is being recorded over the vesting period.

The estimated fair value of the Company’s stock-based awards, less expected annual forfeitures, is amortized over the awards’ service period. The total unrecognized compensation cost for unvested outstanding stock options was $3.3 million for the three months ended June 30, 2013. This expense will be recognized over a weighted average expense period of approximately 1.9 years. The total unrecognized compensation cost for unvested outstanding restricted stock was $4.6 million for the three months ended June 30, 2013. This expense will be recognized over a weighted average expense period of approximately 1.3 years.

The weighted-average assumptions used in the Black-Scholes valuation model for stock options granted during the three months ended June 30, 2013 and 2012 are as follows:


	Three months ended June 30,
	2013			2012
Expected volatility		74.6	%		72.0	%
Risk-free interest rate		1.7	%		0.9	%
Expected life (years)		5.9			5.9
Dividend yield		None			None

The expected volatility rate was estimated based on an equal weighting of the historical volatility of the Company’s common stock and the implied volatility of the Company’s traded options. The expected term was estimated based on an analysis of the Company’s historical experience of exercise, cancellation, and expiration patterns. The risk-free interest rate is based on the average of the five and seven year United States Treasury rates.

Computation of Net (Loss) Income Per Common Share

3 Months Ended

Jun. 30, 2013

Earnings Per Share [Abstract]

Computation of Net (Loss) Income Per Common Share

3.	Computation of Net (Loss) Income per Common Share

Basic net loss per share (“EPS”) is computed by dividing net loss by the weighted-average number of common shares outstanding for the period. Where applicable, diluted EPS is computed by dividing the net loss by the weighted-average number of common shares and dilutive common equivalent shares outstanding during the period, calculated using the treasury stock method. Common equivalent shares include the effect of restricted stock, exercise of stock options and warrants and contingently issuable shares. For the three months ended June 30, 2013, 6.1 million shares were not included in the calculation of diluted EPS as they were considered anti-dilutive, of which 2.9 million relate to unvested stock options and 3.2 million relate to the issuance of warrants. For the three months ended June 30, 2012, 6.3 million shares were not included in the calculation of diluted EPS as they were considered anti-dilutive, of which 3.1 million relate to unvested stock options and 3.2 million relate to the issue of warrants.

The following table reconciles the numerators and denominators of the earnings per share calculation for the three months ended June 30, 2013 and 2012 (in thousands, except per share data):


	Three months ended June 30,
	2013			2012

Numerator:
Net loss	$	(10,513	)	$	(10,275	)

Denominator:
Weighted-average shares of common stock outstanding		60,463			51,997
Weighted-average shares subject to repurchase		(2,163	)		(806	)

Shares used in per-share calculation — basic		58,300			51,191
Shares used in per-share calculation — diluted		58,300			51,191

Net loss per share — basic	$	(0.18	)	$	(0.20	)

Net loss per share — diluted	$	(0.18	)	$	(0.20	)

Fair Value Measurements

3 Months Ended

Jun. 30, 2013

Fair Value Disclosures [Abstract]

Fair Value Measurements

4.	Fair Value Measurements

In January 2010, the Financial Accounting Standards Board (“FASB”) issued guidance related to disclosures of fair value measurements. The guidance requires gross presentation of activity within the Level 3 measurement roll-forward and details of transfers in and out of Level 1 and 2 measurements. It also clarifies two existing disclosure requirements on the level of disaggregation of fair value measurements and disclosures on inputs and valuation techniques. A change in the hierarchy of an investment from its current level will be reflected in the period during which the pricing methodology of such investment changes. Disclosure of the transfer of securities from Level 1 to Level 2 or Level 3 will be made in the event that the related security is significant to total cash and investments. The Company did not have any transfers of assets and liabilities between Level 1, Level 2 and Level 3 of the fair value measurement hierarchy during the three months ended June 30, 2013.

A valuation hierarchy for disclosure of the inputs to valuation used to measure fair value has been established. This hierarchy prioritizes the inputs into three broad levels as follows:


Level 1 -		Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2 -		Inputs include quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability, and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs).

Level 3 -		Unobservable inputs that reflect the Company’s assumptions that market participants would use in pricing the asset or liability. The Company develops these inputs based on the best information available, including its own data.

A financial asset’s or liability’s classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement.

The following table provides the assets carried at fair value, measured as of June 30, 2013 and March 31, 2013 (in thousands):


	Total Carrying Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
June 30, 2013:
Assets:
Cash equivalents	$	18,658	$	18,658	$	—	$	—
Liabilities:
Derivative liability	$	477	$	—	$	—	$	477
Warrants	$	3,216	$	—	$	—	$	3,216

	Total Carrying Value		Quoted Prices in Active Markets (Level 1)		Using Significant Other Observable Inputs (Level 2)		Using Significant Unobservable Inputs (Level 3)
March 31, 2013:
Assets:
Cash equivalents	$	18,649	$	18,649	$	—	$	—
Liabilities:
Derivative liability	$	529	$	—	$	—	$	529
Warrants	$	3,633	$	—	$	—	$	3,633

The table below reflects the activity for the Company’s major classes of liabilities measured at fair value for the period ended June 30, 2013 (in thousands).


	Derivative Liability			Warrants
April 1, 2013	$	529		$	3,633
Mark to market adjustment		(52	)		(417	)

Balance at June 30, 2013	$	477		$	3,216


	Derivative Liability			Warrants
April 1, 2012	$	—		$	—
Valuation of derivative liability		3,779			—
Warrant issuance with Senior Convertible Notes		—			7,018
Warrant issuance with Senior Secured Term Loan		—			380
Valuation of derivative liability attributable to modification		542			—
Mark to market adjustment		(3,792	)		(3,765	)

Balance at March 31, 2013	$	529		$	3,633

Valuation Techniques

Cash Equivalents

Cash equivalents consist of highly liquid instruments with maturities of three months or less that are regarded as high quality, low risk investments and are measured using such inputs as quoted prices, and are classified within Level 1 of the valuation hierarchy. Cash equivalents consist principally of certificates of deposits and money market accounts.

Derivative Liability

The Company has identified all of the derivatives (“Derivative Liability”) associated with the Exchanged Note which include put rights to require the investor to acquire an additional $15.0 million convertible note and additional warrants, holder change of control redemption rights, issuer optional redemption rights, sale redemption rights and a right to make payment in the form of stock rather than cash if certain equity conditions are met. The Derivative Liability is subject to revaluation at each balance sheet date, and any change in fair value will be recorded as a change in fair value in other income (expense) until the earlier of its exercise or expiration. The Company relies on assumptions in a lattice model to determine the fair value of Derivative Liability. The Company has appropriately valued the Derivative Liability within Level 3 of the valuation hierarchy. See Note 10, “Debt”, for discussion on the Exchanged Note, Derivative Liability and valuation assumptions used.

Warrants

Warrants were issued in conjunction with the Initial Note and the Term Loan. See Note 10, “Debt”, for additional information on warrants. These warrants are subject to revaluation at each balance sheet date, and any change in fair value will be recorded as a change in fair value in other income (expense) until the earlier of their exercise or expiration.

The Company relies on assumptions used in a lattice model to determine the fair value of warrants. The Company has appropriately valued the warrants within Level 3 of the valuation hierarchy. See Note 11, “Warrants and Derivative Liabilities”, for a discussion of the warrants and the valuation assumptions used.

Accounts Receivable

3 Months Ended

Jun. 30, 2013

Receivables [Abstract]

Accounts Receivable

5.	Accounts Receivable

Accounts receivable at June 30, 2013 and March 31, 2013 consisted of the following (in thousands):


	June 30, 2013		March 31, 2013
Accounts receivable (billed)	$	9,225	$	17,222
Accounts receivable (unbilled)		1,863		1,642
Less: Allowance for doubtful accounts		—		—

Accounts receivable, net	$	11,088	$	18,864

Inventory

3 Months Ended

Jun. 30, 2013

Inventory Disclosure [Abstract]

Inventory

6.	Inventory

The components of inventory at June 30, 2013 and March 31, 2013 are as follows (in thousands):


	June 30, 2013		March 31, 2013
Raw materials	$	6,423	$	5,966
Work-in-process		3,730		3,427
Finished goods		17,914		21,655
Deferred program costs		2,685		2,425

Net inventory	$	30,752	$	33,473

For the three months ended June 30, 2013, the Company recorded an inventory write-down of approximately $0.2 million based on evaluating its ending inventory on hand for excess quantities and obsolescence.

Deferred program costs as of June 30, 2013 and March 31, 2013 primarily represent costs incurred on programs accounted for under contract accounting where the Company needs to complete development programs before revenue and costs will be recognized, respectively.

Accounts Payable and Accrued Expenses

3 Months Ended

Jun. 30, 2013

Payables And Accruals [Abstract]

Accounts Payable and Accrued Expenses

7.	Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consisted of the following (in thousands):


	June 30,		March 31,
	2013		2013
Accounts payable	$	4,174	$	7,146
Accrued miscellaneous expenses		9,419		9,142
Accrued VAT		1,517		809
Accrued outside services		2,744		2,251
Accrued subcontractor program costs		512		2,442
Accrued compensation		4,153		5,506
Income taxes payable		175		133
Accrued warranty		2,787		2,709

Total	$	25,481	$	30,138

The Company generally provides a one to three year warranty on its products, commencing upon installation. A provision is recorded upon revenue recognition to cost of revenues for estimated warranty expense based on historical experience.

Product warranty activity was as follows (in thousands):


	Three months ended June 30,
	2013			2012
Balance at beginning of period	$	2,709		$	5,896
Accruals for warranties during the period		152			(167	)
Settlements during the period		(74	)		(229	)

Balance at end of period	$	2,787		$	5,500

Income Taxes	3 Months Ended
Income Taxes	Jun. 30, 2013
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes For the three months ended June 30, 2013 and 2012, the Company recorded an income tax expense of $0.1 million and income tax benefit of $0.8 million, respectively. The income tax expense for the three months ended June 30, 2013, was primarily due to income taxes in the Company’s foreign jurisdictions. The income tax benefit for the three months ended June 30, 2012, was primarily due to a refund of Chinese income taxes of $0.9 million.

Restructuring

3 Months Ended

Jun. 30, 2013

Restructuring And Related Activities [Abstract]

Restructuring

9.	Restructuring

The Company accounts for charges resulting from operational restructuring actions in accordance with ASC Topic 420, Exit or Disposal Cost Obligations (“ASC 420”) and ASC Topic 712, Compensation—Nonretirement Postemployment Benefits (“ASC 712”). In accounting for these obligations, the Company is required to make assumptions related to the amounts of employee severance, benefits, and related costs and the time period over which leased facilities will remain vacant, sublease terms, sublease rates and discount rates. Estimates and assumptions are based on the best information available at the time the obligation arises. These estimates are reviewed and revised as facts and circumstances dictate; changes in these estimates could have a material effect on the amount accrued on the consolidated balance sheet.

During the years ended March 31, 2013 and March 31, 2012, the Company initiated restructuring activities, approved by the Board of Directors, in order to reorganize its global operations, streamline various functions of the business, and reduce its global workforce to better reflect the demand for its products. The Company undertook an additional workforce reduction in July 2013, (See Note 16—“Subsequent Events”, for additional information related to the July reduction). These activities resulted in the reduction of its global workforce by approximately 57%, in aggregate. During the three months ended June 30, 2013 and 2012, the Company incurred restructuring costs of less than $0.1 million and $0.1 million, respectively. The remaining balance of accrued restructuring is expected to be paid through June 2014.

The following table presents restructuring charges and cash payments (in thousands):


	Severance pay and benefits			Facility exit costs			Total
Three months ended June 30, 2013
Accrued restructuring balance at April 1, 2013	$	199			—		$	199
Charges to operations		13			—			13
Cash payments		(136	)		—			(136	)

Accrued restructuring balance at June 30, 2013	$	76		$	—		$	76


Three months ended June 30, 2012
Accrued restructuring balance at April 1, 2012	$	680		$	294		$	974
Charges to operations		167			(39	)		128
Cash payments		(269	)		(255	)		(524	)

Accrued restructuring balance at June 30, 2012	$	578		$	—		$	578

All restructuring charges discussed above are included within restructuring and impairments in the Company’s unaudited condensed consolidated statements of operations. The Company includes accrued restructuring within accounts payable and accrued expenses in the unaudited condensed consolidated balance sheets.

Debt

3 Months Ended

Jun. 30, 2013

Debt Disclosure [Abstract]

Debt

10.

Debt

Senior Convertible Note

On April 4, 2012, the Company entered into a Securities Purchase Agreement with Capital Ventures International (“CVI”), an affiliate of Heights Capital Management (the “Purchase Agreement”) and completed a private placement of the Initial Note, a 7% unsecured senior convertible note. After fees and expenses, the net proceeds of the Initial Note were $23.2 million. The Initial Note had an initial conversion price of $4.85 per share, representing a premium of approximately 20% over AMSC’s closing price on April 3, 2012. The Initial Note was payable in monthly installments beginning four months from issuance and ending on October 4, 2014. Monthly payments were payable in cash or the Company’s common stock at the option of the Company, subject to certain trading volume, stock price and other conditions. CVI could have also elected to defer receipt of monthly installment payments at its option. Any deferred installment payments would have continued to accrue interest. The Company registered 10,262,311 shares of common stock which may be used as payment for principal and interest in lieu of cash for resale under the Securities Act as required under a Registration Rights Agreement with CVI.

The Company accounted for the Initial Note as an instrument that has the characteristics of a debt host contract containing several embedded derivative features that would require bifurcation and separate accounting as a derivative instrument pursuant to the provisions of ASC 815. The Company elected not to use the fair value option for the aggregate amount of the Exchanged Note and recorded the liability at its stated value on the date of issuance with no changes in fair value reported in subsequent periods.

The Company has identified the following derivatives associated with the Initial Note: holder change of control redemption rights; issuer optional redemption rights; sale redemption rights and a feature to convert the Initial Note into equity at the holder’s option. The Company valued these derivatives at $3.8 million upon issuance of the Initial Note. (See Note 11, “Warrants and Derivative Liabilities,” for additional information regarding derivative liabilities.)

In conjunction with the Initial Note, CVI received a warrant to purchase approximately 3.1 million additional shares of common stock exercisable at a strike price of $5.45 per share, subject to adjustment, until October 4, 2017. Due to certain adjustment provisions within the warrant, it qualified for liability accounting and had a fair value of $7.0 million upon issuance. The Company recorded the value as a debt discount and a warrant liability. (See Note 11, “Warrants and Derivative Liabilities,” for additional information regarding the warrant.)

The process of valuing financial and derivative instruments utilizes facts and circumstances as of the measurement date as well as certain inputs, assumptions, and judgments that may affect the estimated fair value of the instruments. Upon issuance of the Initial Note, the Company determined the initial carrying value of the Initial Note to be $25.0 million. In addition, the Company also incurred $1.8 million of legal and origination costs as of the year ended March 31, 2013, which have been recorded as a discount on the Initial Note.

On December 20, 2012, the Company entered into an Amendment and Exchange Agreement, (the “Amendment”) with CVI, which amended the Purchase Agreement. Pursuant to the Amendment, the Company and CVI exchanged the Initial Note for the Exchanged Note. At the time of the exchange, the Exchanged Note had the same principal amount and accrued interest as the Initial Note. The Exchanged Note is convertible into the Company’s common stock and has the same scheduled monthly installment payments as the Initial Note. The Exchanged Note provides the Company with additional flexibility to make monthly installment payments in shares of the Company’s common stock. The Company retains the ability to repay the Exchanged Note in cash. Specifically, the amendments to the Exchanged Note:

•

Allow the Company to convert, subject to the satisfaction of certain conditions set forth in the Exchanged Note, (a) at least $2.5 million of the approximately $5.3 million installment amount payable with respect to the January 2013 installment date (including approximately $4.2 million of deferred installment amounts from the period September 4, 2012 to December 3, 2012) into shares of the Company’s common stock (on December 21, 2012 the Company converted $3.8 million in deferred installment amount principal and interest and issued 1,715,443 shares of common stock), and (b) the balance of the January 2013 installment amount in equal amounts on each of the February and March 2013 installment dates;

•

Reduce the price failure equity condition with respect to a particular date of determination from $2.50 to $1.00;

•

Reduce the aggregate daily dollar trading volume equity condition required for at least 25 of the 30 consecutive trading days immediately preceding a date of determination from $1,500,000 to $850,000 per trading day. In addition, if the aggregate daily dollar trading volume is between $50,000 and $850,000, the Company may still convert into common stock a portion of an installment amount payable with respect to an installment date equal to the quotient of (x) the aggregate daily dollar trading volume, divided by (y) $850,000;

•

Increase CVI’s beneficial ownership limitation under the Exchanged Note from 4.99% to 9.99%; and

•

Reduce the conversion price, from $4.85 per share of the Company’s common stock to $3.19 per share of the Company’s common stock, subject to certain price-based and other anti-dilution adjustments.

The Company assessed the changes in the Exchanged Note and accounted for it as a modification of the Initial Note. Therefore, the Company determined the incremental value of the derivative instruments, as a result of the Exchanged Note, as having a reduced conversion price. As a result of the re-valuation, the Company recorded a $0.5 million increase in the value of the derivative liability and additional debt discount. At the modification date, the value of the derivative liability was $1.5 million. The total debt discount, including the embedded derivatives in the Initial Note, the incremental value of embedded derivatives in the Exchanged Note, warrant and legal and origination costs of $13.1 million is being amortized into interest expense over the term of the Exchanged Note using the effective interest method. Under this method, interest expense is recognized each period until the debt instruments reach maturity. If the maturity of the Exchanged Note is accelerated because of prepayment, then the amortization will be accelerated. During the three months ended June 30, 2013, and 2012 the Company recorded non-cash interest expense for amortization of the debt discount related to the convertible notes of $1.5 million and $2.2 million, respectively.

Provided certain equity conditions are met, the Company may elect to repay principal and interest in shares of the Company’s common stock. If the Company elects to make a payment in shares of the Company’s common stock, the number of shares to be issued is determined by dividing the amount of such payment by 85% of the lessor of the average volume-weighted average price (“VWAP”) of the 10 consecutive days immediately preceding the payment date or the VWAP price on the day preceding the payment date (the “Market Price”). The Company records the difference between the closing price of its common stock on the day preceding the payment date and the Market Price as a discount on the fair value of its shares. During the three months ended June 30, 2013, the Company recorded $0.1 million of non-cash interest expense related to installment payments made by issuing the Company’s common stock at a discount.

The Exchanged Note and Purchase Agreement contain certain covenants and restrictions, including, among others, that for so long as the Exchanged Note is outstanding, the Company will not incur any indebtedness (other than permitted indebtedness under the Exchanged Note), permit liens on its properties (other than permitted liens under the Exchanged Note), make payments on junior securities or declare dividends. The Exchanged Note also contains limitations on the transfer of certain assets. Events of default under the Exchanged Note include failure to pay principal or interest as due on the Exchanged Note, failure to deliver registered shares of common stock upon the holders request for conversion of part or all of the Exchanged Note, failure to maintain the Company’s common stock eligible for trading on defined markets, cross defaults to other material indebtedness, receipt of uninsured judgments against the Company in excess of defined limits and other administrative covenants, including the Term Loan discussed below, as defined in the Exchanged Note and related documentation. Upon an event of default, the holders may require the Company to redeem all or any portion of the outstanding principal amount of the Exchanged Note in cash plus a penalty as specified in the agreement. Also, if the Company fails to maintain an effective registration statement covering common stock to be used in settling obligations under the Exchanged Note, the Company will be required to pay a penalty as specified in the agreement.

Senior Secured Term Loan

On June 5, 2012, the Company entered into a Term Loan with Hercules Technology Growth Capital, Inc. (“Hercules”), under which the Company borrowed $10.0 million (the “Term Loan”). After the closing fees and expenses, the net proceeds to the Company were $9.7 million. The Term Loan bears an interest rate equal to 11% plus the percentage, if any, by which the prime rate as reported by The Wall Street Journal exceeds 3.75%. The Company made interest-only payments from July 1, 2012 through October 31, 2012, after which the Company repays the loan in equal monthly installments ending on December 1, 2014. The Term Loan is secured by substantially all of the Company’s existing and future assets, including a mortgage on real property owned by the Company’s wholly-owned subsidiary, ASC Devens LLC, and located at 64 Jackson Road, Devens, Massachusetts. In addition, Hercules received a warrant to purchase 139,276 shares of common stock, exercisable at an initial strike price of $3.59 per share, subject to adjustment, until December 5, 2017. Due to certain adjustment provisions within the warrant, it qualified for liability accounting and the fair value of $0.4 million was recorded upon issuance, which the Company recorded as a debt discount and a warrant liability. (See Note 11, “Warrants and Derivative Liabilities,” for a discussion on warrants and the valuation assumptions used.) The Company will pay an end of term fee of $0.5 million upon the earlier of maturity or prepayment of the loan. The Company has accrued this as of the year ended March 31, 2013 and recorded a corresponding amount into the debt discount. In addition, the Company incurred $0.3 million of legal and origination costs in the year ended March 31, 2013, which have been recorded as a debt discount. The total debt discount including the warrant, end of term fee and legal and origination costs of $1.2 million is being amortized into interest expense over the term of the Term Loan using the effective interest method. Under this method, interest expense is recognized each period until the debt instrument reaches maturity. If the maturity of the Term Loan is accelerated because of prepayment, then the amortization will be accelerated. During the three months ended June 30, 2013 and 2012, the Company recorded non-cash interest expense for amortization of the debt discount related to the Term Loan of $0.1 million and $0.1 million, respectively.

The Term Loan contains certain covenants that restrict the Company’s ability to, among other things, incur or assume certain debt, merge or consolidate, materially change the nature of our business, make certain investments, acquire or dispose of certain assets, make guaranties or grant liens on its assets, make certain loans, advances or investments, declare dividends or make distributions or enter into transactions with affiliates. In addition, the Term Loan contains a covenant that requires the Company to maintain a minimum unrestricted cash balance in the United States of at least $10.0 million at the inception of the Term Loan, which decreased starting November 1, 2012 and monthly thereafter by the amount of principal paid. The events of default under the Term Loan include, but are not limited to, failure to pay amounts due, breaches of covenants, bankruptcy events, cross defaults under other material indebtedness and the occurrence of a material adverse effect and/or change in control. In the case of a continuing event of default, the Lender may, among other remedies, declare due all unpaid principal amounts outstanding and any accrued but unpaid interest and foreclose on all collateral granted to the Lender as security under the Term Loan.

Although the Company believes that it is in and expects to remain in compliance with the covenants and restrictions under the Exchanged Notes and Term Loan as of the date of this Quarterly Report on Form 10-Q, there can be no assurance that the Company will continue to be in compliance.

Interest expense on the Exchanged Note and Term Loan for the three months ended June 30, 2013 and 2012 was $2.1 million, and $2.7 million, respectively, which included $1.7 million and $2.3 million, respectively, of non-cash interest expense related to the amortization of the debt discount on the Exchanged Note and Term Loan and payment of the Exchanged Note in Company common stock at a discount.

Warrants and Derivative Liabilities

3 Months Ended

Jun. 30, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Warrants and Derivative Liabilities

11.

Warrants and Derivative Liabilities

On April 4, 2012, the Company entered into a Purchase Agreement for the Initial Note and on December 20, 2012, the Company entered into the Amendment pursuant to which it exchanged the Initial Note for the Exchanged Note, as described in Note 10. The Initial Note included a warrant to purchase 3,094,060 million shares of the Company’s common stock. The warrant is exercisable at any time on or after the date that is six months after the issuance of the warrant and entitles CVI to purchase shares of the Company’s common stock for a period of five years from the initial date the warrant becomes exercisable at a price equal to $5.45 per share, subject to certain price-based and other anti-dilution adjustments. The warrant may not be exercised if, after giving effect to the conversion, CVI together with its affiliates would beneficially own in excess of 4.99% of the Company’s common stock. This percentage may be raised to any other percentage not in excess of 9.99% at the option of CVI, upon at least 61-days prior notice to the Company, or lowered to any other percentage, at the option of CVI, at any time.

The Company calculated the fair value of the derivative liabilities and warrants utilizing an integrated lattice model. The lattice model is an option pricing model that involves the construction of a binomial tree to show the different paths that the underlying asset may take over the option’s life. A lattice model can take into account expected changes in various parameters such as volatility over the life of the options, providing more accurate estimates of option prices than the Black-Scholes model.

The Company accounts for the warrant as a liability due to certain adjustment provisions within the warrant, which requires that it be recorded at fair value. The warrant is subject to revaluation at each balance sheet date and any change in fair value will be recorded as a change in fair value in other income (expense) until the earlier of expiration or its exercise at which time the warrant liability will be reclassified to equity. Following is a summary of the key assumptions used to calculate the fair value of the warrant:


	June 30, 2013
Fiscal Year 2013

Risk-free interest rate		1.13	%
Expected annual dividend yield		0.0	%
Expected volatility		71.9	%
Term (years)		4.27
Fair Value	$	3.0 million


	March 31,			December 31,			September 30,			June 30,			April 4,
	2013			2012			2012			2012			2012
Fiscal Year 2012

Risk-free interest rate		0.67	%		0.75	%		0.63	%		0.77	%		1.19	%
Expected annual dividend yield		0.0	%		0.0	%		0.0	%		0.0	%		0.0	%
Expected volatility		71.7	%		80.6	%		80.9	%		80.8	%		80.0	%
Term (years)		4.51			4.76			5.01			5.28			5.5
Fair Value	$	3.4 million		$	4.4 million		$	7.1 million		$	8.6 million		$	7.0 million

The Company recorded the change in the fair value of the CVI warrant of $0.4 million gain and $1.6 million loss, to change in fair value of derivatives and warrants in the three months ended June 30, 2013 and 2012, respectively.

The Company determined certain embedded derivatives issued with the convertible notes required accounting as a liability, which requires they be accounted for as a standalone liability subject to revaluation at each balance sheet date with changes in fair value recorded as change in fair value of derivatives and warrants until the earlier of exercise or expiration.

The terms of the debt modification reduced the conversion price of the Initial Note from $4.85 per share to $3.19 per share in the Exchanged Note. As a result the Company revalued these derivatives pre- and post-modification and recorded the difference of $0.5 million as a debt discount and a derivative liability. (See Note 10, “Debt,” for further discussion). Following is a summary of the key assumptions used to value the convertible notes derivative feature:


	June 30,
	2013
Fiscal Year 2013

Principal Outstanding (000’s)	$	14,389
Stock Price	$	2.64
Percentage Volume Condition Met		87.5	%
Expected Volatility		65.8	%
Risk Free Rate		0.21	%
Bond Yield		16.7	%
Recovery Rate		37.0	%
Redeemable		yes
Total Time (years)		1.26
Dilution Effect		yes
Fair Value	$	0.5 million
Fair Value as a Percent of Par		3.3	%


							Post- modification			Pre-modification
	March 31,			December 31,			December 20,			December 20,			September 30,			June 30,			April 4,
	2013			2012			2012			2012			2012			2012			2012
Fiscal Year 2012

Principal Outstanding (000’s)	$	15,380		$	20,944		$	20,944		$	24,617		$	24,191		$	25,278		$	25,000
Stock Price	$	2.67		$	2.62		$	2.95		$	2.95		$	4.15		$	4.68		$	3.97
Percentage Volume Condition Met		80.5	%		94.5	%		94.9	%		28.6	%		51.0	%		75.2	%		85.9	%
Expected Volatility		66.9	%		73.5	%		72.5	%		72.5	%		70.0	%		71.0	%		75.0	%
Risk Free Rate		0.20	%		0.23	%		0.25	%		0.25	%		0.23	%		0.33	%		0.44	%
Bond Yield		16.5	%		16.5	%		16.5	%		16.5	%		15.0	%		16.0	%		15.0	%
Recovery Rate		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%
Redeemable		yes			yes			yes			yes			yes			yes			yes
Total Time (years)		1.51			1.76			1.79			1.79			2.01			2.28			2.5
Dilution Effect		yes			yes			yes			yes			yes			yes			yes
Fair Value as a Percent of Par		3.4	%		4.9	%		7.1	%		3.9	%		11.4	%		17.9	%		15.1	%
Fair Value	$	0.5 million		$	1.0 million		$	1.5 million		$	0.9 million		$	2.8 million		$	4.5 million		$	3.8 million

Based on historical volume-weighted average price (“VWAP”) of the Company’s common stock as well as the historic average dollar trading volume of the Company’s common stock, the percentage volume condition is the probability that the Company will convert monthly installment payments into the Company’s common stock. The expected volatility rate was estimated based on an equal weighting of the historical volatility of the Company’s common stock and the implied volatility of the Company’s traded options. To determine the risk-free interest rate, an interpolated rate was used based on the one, two and three-year United States Treasury rates. The bond yield was estimated using comparable corporate debt and yield information. The recovery rate of the Exchanged Note was estimated by reviewing historical corporate debt that went into default. The bond is redeemable by the Company at any point after the one-year anniversary of the grant date provided certain provisions within the note. The total time is based on the actual 30-month contractual terms. It was determined that there is a dilution effect based on the Company’s ability to make payments in shares of common stock.

The Company recorded the change in the fair value of the derivative liabilities of $0.1 million gain and $0.7 million loss, to changes in fair value of derivatives and warrants in the three months ended June 30, 2013 and 2012, respectively.

On June 5, 2012, the Company entered into a Loan and Security Agreement with Hercules (see Note 10, “Debt,” for additional information regarding the Loan and Security Agreement). In conjunction with this agreement, the Company issued a warrant to purchase 139,276 shares of the Company’s common stock. The warrant is exercisable at any time after the issuance of the warrant and expires on December 5, 2017, at a price equal to $3.59 per share subject to certain price-based and other anti-dilution adjustments.

The Company accounts for the warrant as a liability due to certain provisions within the warrant, which requires that it be recorded at fair value. The warrant is subject to revaluation at each balance sheet date and any change in fair value will be recorded as changes in fair value of derivatives and warrants until the earlier of expiration or its exercise at which time the warrant liability will be reclassified to equity. Following is a summary of the key assumptions used to calculate the fair value of the warrant:


	June 30,
	2013
Fiscal Year 2013

Risk-free interest rate		1.20	%
Expected annual dividend yield		—	%
Expected volatility		72.3	%
Term (years)		4.43
Fair Value	$	0.2 million


	March 31,			December 31,			September 30,			June 30,			June 5,
	2013			2012			2012			2012			2012
Fiscal Year 2012

Risk-free interest rate		0.70	%		0.75	%		0.64	%		0.80	%		0.77	%
Expected annual dividend yield		—	%		—	%		—	%		—	%		—	%
Expected volatility		72.01	%		80.14	%		81.18	%		80.32	%		79.99	%
Term (years)		4.68			4.93			5.18			5.44			5.5
Fair Value	$	0.2 million		$	0.2 million		$	0.4 million		$	0.5 million		$	0.4 million

The Company prepared its estimates for the assumptions used to determine the fair value of the warrants issued in conjunction with both the Convertible Note and Term Loan utilizing the respective terms of the warrants with similar inputs, as described above.

The Company recorded a loss from the change in the fair value of the Hercules warrant of $0.1 million, during the three months ended June 30, 2012.

Commitments and Contingencies

3 Months Ended

Jun. 30, 2013

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

12.

Commitments and Contingencies

Commitments

Purchase Commitments

The Company periodically enters into non-cancelable purchase contracts in order to ensure the availability of materials to support production of its products. Purchase commitments represent enforceable and legally binding agreements with suppliers to purchase goods or services. The Company periodically assesses the need to provide for impairment on these purchase contracts and record a loss on purchase commitments when required. As of June 30, 2013, the Company reported a liability for adverse purchase commitments of $1.2 million. During the three months ended June 30, 2013, the Company reduced its accrual for adverse purchase commitments by $0.3 million due to payments to certain vendors.

Legal Contingencies

From time to time, the Company is involved in legal and administrative proceedings and claims of various types. The Company records a liability in its consolidated financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in a liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in its consolidated financial statements.

Between April 6, 2011 and May 12, 2011, seven putative securities class action complaints were filed against the Company and two of its officers in the United States District Court for the District of Massachusetts; one complaint additionally asserted claims against the underwriters who participated in our November 12, 2010 securities offering. On June 7, 2011, the United States District Court for the District of Massachusetts consolidated these actions under the caption Lenartz v. American Superconductor Corporation, et al., Docket No. 1:11-cv-10582-WGY. On August 31, 2011, Lead Plaintiff, the Plumbers and Pipefitters National Pension Fund, filed a consolidated amended complaint against the Company, its officers and directors, and the underwriters who participated in our November 12, 2010 securities offering, asserting claims under sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated under the Securities Exchange Act of 1934 (the “Exchange Act”), as well as under sections 11, 12(a)(2) and 15 of the Securities Act of 1933 (the “Securities Act”). The complaint alleges that during the relevant class period, the Company and its officers omitted to state material facts and made materially false and misleading statements relating to, among other things, its projected and recognized revenues and earnings, as well as its relationship with Sinovel Wind Group Co., Ltd. that artificially inflated the value of the Company’s stock price. The complaint further alleges that the Company’s November 12, 2010 securities offering contained untrue statements of material facts and omitted to state material facts required to be stated therein. The plaintiffs seek unspecified damages, rescindment of the Company’s November 12, 2010 securities offering, and an award of costs and expenses, including attorney’s fees. All defendants moved to dismiss the consolidated amended complaint. On December 16, 2011, the district court issued a summary order declining to dismiss the Securities Act claims against the Company and its officers, and taking under advisement the motion to dismiss the Exchange Act claims against the Company and its officers and the motion to dismiss the Securities Act claims made against the underwriters. On July 26, 2012, the district court dismissed the Exchange Act claims against the Company and its officers and denied the motion to dismiss the Securities Act claims made against the underwriters. On May 17, 2013, the parties informed the district court that they had reached a settlement in principle, and requested a 30-day stay of the proceedings while the specific terms of the settlement continue to be negotiated. Based on the Company’s assessment of the probable losses on this claim, the Company has recorded a loss contingency of $1.8 million as of June 30, 2013.

Between May 4, 2011 and June 17, 2011, four putative shareholder derivative complaints were filed against the Company (as a nominal defendant) and certain of its directors in the United States District Court for the District of Massachusetts. On July 5, 2011, the District Court consolidated three of these actions, and that matter is now captioned In re American Superconductor Corporation Derivative Litigation, Docket No. 1:11-cv-10784-WGY. On June 1, 2011, the plaintiff in the fourth action, Marlborough Family Revocable Trust v. Yurek, et al., moved to voluntarily dismiss its complaint and refiled its complaint in Superior Court for the Commonwealth of Massachusetts, Middlesex County. On September 7, 2011, the Marlborough action and another putative shareholder derivative complaint filed in Superior Court for the Commonwealth of Massachusetts were consolidated. That consolidated matter is captioned In re American Superconductor Corporation Shareholder Derivative Litigation, Docket No. 11-1961. On January 12, 2012, an additional shareholder derivative complaint was filed in the Court of Chancery for the State of Delaware. That matter is captioned Krasnoff v. Budhraja, et al., Docket No. 7171. The allegations of the derivative complaints mirror the allegations made in the putative class action complaints described above. The plaintiffs purport to assert claims against the director defendants for breach of fiduciary duty, abuse of control, gross mismanagement, unjust enrichment and corporate waste. The plaintiffs seek unspecified damages on behalf of the Company, as well as an award of costs and expenses, including attorney’s fees.

If a matter is both probable to result in liability and the amount of loss can be reasonably estimated, we estimate and disclose the possible loss or range of possible loss. With respect to the above referenced shareholder derivative litigation matters, an estimate of loss or range of loss cannot be made. There are numerous factors that make it difficult to meaningfully estimate possible loss or range of loss at this stage of these litigation matters, including that: the proceedings are in relatively early stages, there are significant factual and legal issues to be resolved, information obtained or rulings made during the lawsuits could affect the methodology for calculation of rescission and the related statutory interest rate. In addition, with respect to claims where damages are the requested relief, no amount of loss or damages has been specified. Therefore, the Company is unable at this time to estimate possible losses. The Company believes that these litigations are without merit, and it intends to defend these actions vigorously.

On September 13, 2011, the Company commenced a series of legal actions in China against Sinovel Wind Group Co. Ltd. (“Sinovel”). The Company’s Chinese subsidiary, Suzhou AMSC Superconductor Co. Ltd., filed a claim for arbitration with the Beijing Arbitration Commission in accordance with the terms of the Company’s supply contracts with Sinovel. The case is captioned (2011) Jing Zhong An Zi No. 0963. On March 31, 2011, Sinovel refused to accept contracted shipments of 1.5 megawatt, (“MW”) and 3 MW wind turbine core electrical components and spare parts that the Company was prepared to deliver. The Company alleges that these actions constitute material breaches of its contracts because Sinovel did not give it notice that it intended to delay deliveries as required under the contracts. Moreover, the Company alleges that Sinovel has refused to pay past due amounts for prior shipments of core electrical components and spare parts. The Company is seeking compensation for past product shipments and retention (including interest) in the amount of approximately RMB 485 million ($76 million) due to Sinovel’s breaches of its contracts. The Company is also seeking specific performance of our existing contracts as well as reimbursement of all costs and reasonable expenses with respect to the arbitration. The value of the undelivered components under the existing contracts, including the deliveries refused by Sinovel in March 2011, amounts to approximately RMB 4.6 billion ($720 million).

On October 8, 2011, Sinovel filed with the Beijing Arbitration Commission an application under the caption (2011) Jing Zhong An Zi No. 0963, for a counterclaim against the Company for breach of the same contracts under which the Company filed its original arbitration claim. Sinovel claimed, among other things, that the goods supplied by the Company do not conform to the standards specified in the contracts and claimed damages in the amount of approximately RMB 370 million ($58 million). On October 17, 2011, Sinovel filed with the Beijing Arbitration Commission a request for change of counterclaim to increase its damage claim to approximately RMB 1 billion ($157 million). On December 22, 2011, Sinovel filed with the Beijing Arbitration Commission an additional request for change of counterclaim to increase its damages claim to approximately RMB 1.2 billion ($190 million). On February 27, 2012, Sinovel filed with the Beijing Arbitration Commission an application under the caption (2012) Jing Zhong An Zi No. 0157, against the Company for breach of the same contracts under which the Company filed its original arbitration claim. Sinovel claimed, among other things, that the goods supplied by the Company do not conform to the standards specified in the contracts and claimed damages in the amount of approximately RMB 105 million ($17 million). The Company believes that Sinovel’s claims are without merit and it intends to defend these actions vigorously. Since the proceedings in this matter are in relatively early stages, the Company cannot reasonably estimate possible losses or range of losses at this time.

The Company also submitted a civil action application to the Beijing No. 1 Intermediate People’s Court under the caption (2011) Yi Zhong Min Chu Zi No. 15524, against Sinovel for software copyright infringement on September 13, 2011. The application alleges Sinovel’s unauthorized use of portions of the Company’s wind turbine control software source code developed for Sinovel’s 1.5MW wind turbines and the binary code, or upper layer, of the Company’s software for the PM3000 power converters in 1.5MW wind turbines. In July 2011, a former employee of the Company’s Austrian subsidiary was arrested in Austria on charges of economic espionage and fraudulent manipulation of data. In September 2011, the former employee pled guilty to the charges, and was imprisoned. As a result of the Company’s internal investigation and a criminal investigation conducted by Austrian authorities, the Company believes that this former employee was contracted by Sinovel through an intermediary while employed by the Company and improperly obtained and transferred to Sinovel portions of its wind turbine control software source code developed for Sinovel’s 1.5MW wind turbines. Moreover, the Company believes the former employee illegally used source code to develop for Sinovel a software modification to circumvent the encryption and remove technical protection measures on the Company’s PM3000 power converters in 1.5MW wind turbines in the field. The Company is seeking a cease and desist order with respect to the unauthorized copying, installation and use of its software, monetary damages of approximately RMB 38 million ($6 million) for our economic losses and reimbursement of all costs and reasonable expenses. The Beijing No. 1 Intermediate People’s Court accepted the case, which was necessary in order for the case to proceed. In November 2011, Sinovel filed a motion to remove this case from the Beijing No. 1 Intermediate People’s Court and transfer the matter to the Beijing Arbitration Commission. On February 14, 2012, the court denied Sinovel’s motion to remove the case. On February 21, 2012, Sinovel filed an appeal of the Beijing No. 1 Intermediate People’s Court decision to the Beijing Higher People’s Court. On April 25, 2012, the Beijing Higher People’s Court issued a final Civil Ruling which supports the Beijing No.1 Intermediate People’s Court’s civil ruling and rejected Sinovel’s appeal. Sinovel filed an appeal of the Beijing Higher People’s Court’s decision with China’s Supreme People’s Court. A hearing regarding this appeal was held at the Chinese Supreme People’s Court on October 26, 2012. On November 23, 2012, China’s Supreme People’s Court issued a Civil Ruling, holding that (1) it will conduct a re-trial of Sinovel’s appeal, and (2) the lower court’s decision will be stayed pending the re-trial. China’s Supreme People’s Court conducted a re-trial of Sinovel’s appeal on May 29, 2013.

Sinovel filed a new motion on June 18, 2012, to remove this case from the Beijing No. 1 Intermediate People’s Court to the court located in Gansu Province. On October 19, 2012, the court disallowed Sinovel’s motion due to its late filing.

The Company submitted a civil action application to the Beijing Higher People’s Court against Sinovel and certain of its employees for trade secret infringement on September 13, 2011 under the caption (2011) Gao Min Chu Zi No. 4193. The application alleges the defendants’ unauthorized use of portions of the Company’s wind turbine control software source code developed for Sinovel’s 1.5MW wind turbines as described above with respect to the Copyright Action. The Company is seeking monetary damages of RMB 2.9 billion ($453 million) for the trade secret infringement as well as reimbursement of all costs and reasonable expenses. The Beijing Higher People’s Court accepted the case, which was necessary in order for the case to proceed. On December 22, 2011, the Beijing Higher People’s Court transferred this case to the Beijing No. 1 Intermediate People’s Court under the caption (2011) Gao Min Chu Zi No. 4193. On June 7, 2012, the Company received an Acceptance Notice from the Beijing No.1 Intermediate People’s Court under the caption (2012) Yi Zhong Min Chu Zi No.6833. The Company is currently awaiting notice from the Beijing No. 1 Intermediate People’s Court regarding the first hearing date. In August 2012, Sinovel filed a motion to remove this case from the Beijing No. 1 Intermediate People’s Court and transfer the matter to the Beijing Arbitration Commission.

On September 16, 2011, the Company filed a civil copyright infringement complaint in the Hainan Province No. 1 Intermediate People’s Court against Dalian Guotong Electric Co. Ltd. (“Guotong”), a supplier of power converter products to Sinovel, and Huaneng Hainan Power, Inc. (“Huaneng”), a wind farm operator that has purchased Sinovel wind turbines containing Guotong power converter products. The case is captioned (2011) Hainan Yi Zhong Min Chu Zi No. 62. The application alleges that the Company’s PM1000 converters in certain Sinovel wind turbines have been replaced by converters produced by Guotong. Because the Guotong converters are being used in wind turbines containing the Company’s wind turbine control software, the Company believes that its copyrighted software is being infringed. The Company is seeking a cease and desist order with respect to the unauthorized use of its software, monetary damages of RMB 1.2 million ($0.2 million) for its economic losses (with respect to Guotong only) and reimbursement of all costs and reasonable expenses. The court has accepted the case, which was necessary in order for the case to proceed. In addition, upon the request of the defendant Huaneng, Sinovel has been added by the court to this case as a defendant and Huaneng has been released from this case. In December 2011, Sinovel filed a jurisdiction opposition motion requesting dismissal by the Hainan Province No. 1 Intermediate People’s Court, saying the case should be governed by the Beijing Arbitration Commission. On February 3, 2012, the Company received the Civil Ruling from the court, which granted Sinovel’s motion, and dismissed the entire case. The Company appealed the court’s ruling to the Hainan Higher Court, which on April 5, 2012 upheld the decision of the Hainan Province No. 1 Intermediate People’s Court. On April 9, 2012, the Company filed an appeal of the Hainan Higher Court’s decision with China’s Supreme People’s Court. China’s Supreme People’s Court accepted the appeal on May 23, 2012. The case is captioned, (2012) Min Shen Zi No. 630. On December 20, 2012, China’s Supreme People’s Court issued a Civil ruling, holding that (1) it will conduct a re-trial of the Company’s appeal and (2) the lower court’s decision will be stayed pending the re-trial. China’s Supreme People’s Court conducted a re-trial of Sinovel’s appeal on May 29, 2013.

Ghodawat Energy Pvt Ltd (“Ghodawat”), a company registered in India carrying on the business of wind power development, lodged a Request for Arbitration with the Secretariat of the ICC International Court of Arbitration on May 12, 2011 and named AMSC Windtec GmbH (“AMSC Austria”) as the Respondent. Under the Request for Arbitration, Ghodawat alleges that AMSC Austria breached an agreement dated March 19, 2008 pursuant to which AMSC Austria granted a license to Ghodawat to manufacture, use, sell, market, erect, commission and maintain certain wind turbines using its technical information and wind turbine design (the “License Agreement”). Under the Request for Arbitration, Ghodawat’s claims in this arbitration amount to approximately €18 million ($24 million). AMSC Austria filed an Answer to Request for Arbitration and Counterclaim (“Answer and Counterclaim”), in which AMSC Austria denied Ghodawat’s claims in their entirety. AMSC Austria has also submitted counterclaims under the License Agreement against Ghodawat in the amount of approximately €6 million ($9 million). Ghodawat has filed a Reply to Answer to Request for Arbitration and Counterclaim in which it denies AMSC Austria’s counterclaims. On June 3, 2013, the final oral submissions hearing was conducted and the Company believes it will take several months for the Tribunal to render a decision. The Company has recorded a loss contingency based on its assessment of probable losses on this claim; however this amount is immaterial to its consolidated financial statements.

Other

The Company enters into long-term construction contracts with customers that require the Company to obtain performance bonds. The Company is required to deposit an amount equivalent to some or all the face amount of the performance bonds into an escrow account until the termination of the bond. When the performance conditions are met, amounts deposited as collateral for the performance bonds are returned to the Company. In addition, the Company has various contractual arrangements in which minimum quantities of goods or services have been committed to be purchased on an annual basis.

As of June 30, 2013 the Company had $0.8 million of restricted cash included in current assets, and $6.1 million of restricted cash included in long-term assets. These amounts included in restricted cash represent deposits to secure letters of credit for various supply contracts. These deposits are held in interest bearing accounts.

As of June 30, 2013, the Company had one performance bond in support of customer contracts. The total value of the outstanding performance bond is $0.2 million with an expiration date of March 2014. In the event that the payment is made in accordance with the requirements of any of these performance bonds, the Company would record the payment as an offset to revenue.

The Company had an unused, unsecured line of credit consisting of €2.7 million (approximately $3.5 million) in Austria as of June 30, 2013.

Equity Investments

3 Months Ended

Jun. 30, 2013

Equity Method Investments And Joint Ventures [Abstract]

Equity Investments

13.

Equity Investments

Investment in Tres Amigas

On October 9, 2009, the Company made an investment in Tres Amigas LLC, a Delaware limited liability company (“Tres Amigas”), focused on providing the first common interconnection of America’s three power grids to help the country achieve its renewable energy goals and facilitate the smooth, reliable and efficient transfer of green power from region to region, for $1.8 million, consisting of $0.8 million in cash and $1.0 million in AMSC common stock. On January 6, 2011 and May 20, 2011, the Company increased its minority position in Tres Amigas by investing an additional $1.8 million in cash on each date. As of June 30, 2013, the Company holds a 26% ownership interest in Tres Amigas.

The Company’s investment in Tres Amigas is included in other assets on the consolidated balance sheet and the equity in undistributed losses of Tres Amigas is included in other income, net, on the consolidated statements of operations.

The net investment activity for the three months ended June 30, 2013 is as follows (in thousands):


Balance at April 1, 2013	$	2,853
Minority interest in net losses		(248	)

Balance at June 30, 2013	$	2,605

Investment in Blade Dynamics Ltd.

On August 12, 2010, the Company acquired (through its Austrian subsidiary), a minority ownership position in Blade Dynamics Ltd. (“Blade Dynamics”), a designer and manufacturer of advanced wind turbine blades based on proprietary materials and structural technologies, for $8.0 million in cash. As of June 30, 2013, the Company holds a 19% ownership interest in Blade Dynamics.

The investment is carried at the acquisition cost, plus the Company’s equity in undistributed earnings or losses, through December 1, 2012 the date which the company no longer reports undistributed earnings or losses. The Company’s investment in Blade Dynamics is included in other assets on the unaudited condensed consolidated balance sheet and the equity in undistributed losses of Blade Dynamics is included in other income, net, on the unaudited condensed consolidated statements of operations.

The net investment activity for the three months ended June 30, 2013 is as follows (in thousands):


Balance at April 1, 2013	$	4,611
Minority interest in net losses		—
Net foreign exchange rate impact		(69	)

Balance at June 30, 2013	$	4,680

Business Segments

3 Months Ended

Jun. 30, 2013

Segment Reporting [Abstract]

Business Segments

14.

Business Segments

The Company reported its financial results in two reportable business segments: Wind and Grid.

Through its Windtec Solutions, the Wind business segment enables manufacturers to field wind turbines with highly competitive power output, reliability and affordability. The Company supplies advanced power electronics and control systems, licenses its highly engineered wind turbine designs, and provides extensive customer support services to wind turbine manufactures. Its design portfolio includes a broad range of drive trains and power ratings. It provides a broad range of power electronics and software-based control systems that are highly integrated and designed for optimized performance, efficiency, and grid compatibility.

Through its Gridtec Solutions, the Grid business segment enables electric utilities and renewable energy project developers to connect, transmit and distribute power with highly competitive efficiency, reliability and affordability. The Company provides transmission planning services that allow it to identify power grid congestion, poor power quality and other risks, which help the Company determine how its solutions can improve network performance. These services often lead to sales of grid interconnection solutions for wind farms and solar power plants, power quality systems and transmission and distribution cable systems.

The operating results for the two business segments are as follows (in thousands):


	Three months ended June 30,
	2013			2012
Revenues:
Wind	$	14,701		$	16,511
Grid		8,385			12,205

Total	$	23,086		$	28,716


	Three months ended June 30,
	2013			2012
Operating (loss) income:
Wind	$	(1,825	)	$	1,301
Grid		(4,869	)		(5,343	)
Unallocated corporate expenses		(2,156	)		(2,086	)

Total	$	(8,850	)	$	(6,128	)

The accounting policies of the business segments are the same as those for the consolidated Company. The Company’s business segments have been determined in accordance with the Company’s internal management structure, which is organized based on operating activities. The Company evaluates performance based upon several factors, of which the primary financial measures are segment revenues and segment operating (loss) income. The disaggregated financial results of the segments reflect allocation of certain functional expense categories consistent with the basis and manner in which Company management internally disaggregates financial information for the purpose of assisting in making internal operating decisions. In addition, certain corporate expenses which the Company does not believe are specifically attributable or allocable to either of the two business segments have been excluded from the segment operating income.

Unallocated corporate expenses primarily consist of stock-based compensation expense of $2.1 million and $2.0 million for the three months ended June 30, 2013 and 2012, respectively.

Total assets for the two business segments are as follows (in thousands):


	June 30, 2013		March 31, 2013
Wind	$	56,015	$	67,111
Grid		72,252		72,800
Corporate assets		65,926		76,843

Total	$	194,193	$	216,754

The following table sets forth customers who represented 10% or more of the Company’s total revenues for the three months ended June 30, 2013 and 2012:


	Three months ended
	June 30,
	2013			2012
Beijing JINGCHENG New Energy Co., Ltd.		35	%		19	%
INOX Wind Limited		15	%		15	%
Karara Mining Ltd		<1	%		15	%

Recent Accounting Pronouncements

3 Months Ended

Jun. 30, 2013

Accounting Changes And Error Corrections [Abstract]

Recent Accounting Pronouncements

15.

Recent Accounting Pronouncements

In January 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2013-01, Balance Sheet (Topic 210): Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities (ASU 2013-01). The main objective in developing this update is to address implementation issues about the scope of Accounting Standards Update No. 2011-11, Balance Sheet (Topic 210): Disclosures about Offsetting Assets and Liabilities. The update requires entities to disclose information about offsetting and related arrangements of financial instruments and derivative instruments. ASU 2013-01 is effective for our first quarter of fiscal 2014. The Company is currently evaluating the impact of adopting ASU 2013-01, but currently does not believe there will be a significant impact on its consolidated results of operations, financial condition, or cash flows.

In February 2013, the FASB issued ASU No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (ASU 2013-02). The amendments of this ASU require an entity to provide information about the amounts reclassified out of accumulated other comprehensive income (“AOCI”) by component. In addition, an entity is required to present, either on the face of the statement where net income (loss) is presented or in the notes, significant amounts reclassified out of AOCI by the respective line items of net income but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 is effective for fiscal years and interim periods beginning after December 15, 2012. The Company early adopted ASU 2013-02 and it did not have a material impact on the Company’s consolidated results of operations, financial condition, or cash flows.

In March 2013, the FASB issued ASU No. 2013-05, Foreign Currency Matters (Topic 830): Parent’s Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity (ASU 2013-05). The objective of the amendments in this update is to resolve the diversity in practice about whether Subtopic 810-10, Consolidation—Overall, or Subtopic 830-30, Foreign Currency Matters—Translation of Financial Statements, applies to the release of the cumulative translation adjustment into net income when a parent either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business (other than a sale of in substance real estate or conveyance of oil and gas mineral rights) within a foreign entity. In addition, the amendments in this Update resolve the diversity in practice for the treatment of business combinations achieved in involving a foreign entity. ASU 2013-05 is effective for fiscal years and interim periods beginning after December 15, 2013. The Company is currently evaluating the impact of ASU 2013-05, but currently does not believe there will be a significant impact on the Company’s consolidated results of operations, financial condition, or cash flows.

In June 2013, the FASB issued ASU 2013-07, Liquidation Basis of Accounting, to require entities to begin preparing financial statements on a liquidation basis when liquidation is imminent. The guidance requires liquidation accounting when liquidation is imminent, unless an entity is outside the scope of the guidance or it is following a liquidation plan established at its inception. The guidance says liquidation is imminent when either, the party or parties with the authority to approve a liquidation plan do so or other forces (e.g., involuntary bankruptcy) impose a plan for liquidation, and the likelihood that the entity will return from liquidation is remote. The guidance also requires entities using the liquidation basis of accounting to measure their assets at the amount they expect to collect upon sale and liabilities are not remeasured to reflect any anticipation that the entity will be legally released from the obligation. ASU 2013-07 is effective for annual periods beginning after December 15, 2013. The Company is currently evaluating the impact of adopting ASU 2013-07, but currently does not believe there will be an impact on its consolidated results of operations, financial condition, or cash flows.

The Company does not believe that other recently issued accounting pronouncements will have a material impact on its financial statements.

Subsequent Events

3 Months Ended

Jun. 30, 2013

Subsequent Events [Abstract]

Subsequent Events

16.

Subsequent Events

On July 24, 2013, the Company undertook an action to reduce headcount as part of its plan to reduce operating expenses in order to enhance liquidity. The Company reduced its workforce by approximately 7%, impacting primarily selling, engineering and general and administrative functions. The Company expects to record a restructuring charge for severance and other costs of approximately $1.0 million in the second quarter of fiscal 2013.

Stock-Based Compensation (Tables)

3 Months Ended

Jun. 30, 2013

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock-Based Compensation Expense


	Three months ended June 30,
	2013		2012
Cost of revenues	$	205	$	170
Research and development		575		562
Selling, general and administrative		1,355		1,262

Total	$	2,135	$	1,994

Schedule of Weighted Average Assumptions used in Black-Scholes Valuation Model for Stock Options Granted

The weighted-average assumptions used in the Black-Scholes valuation model for stock options granted during the three months ended June 30, 2013 and 2012 are as follows:


	Three months ended June 30,
	2013			2012
Expected volatility		74.6	%		72.0	%
Risk-free interest rate		1.7	%		0.9	%
Expected life (years)		5.9			5.9
Dividend yield		None			None

Computation of Net (Loss) Income Per Common Share (Tables)

3 Months Ended

Jun. 30, 2013

Earnings Per Share [Abstract]

Reconciliation of Numerators and Denominators of EPS Calculation

The following table reconciles the numerators and denominators of the earnings per share calculation for the three months ended June 30, 2013 and 2012 (in thousands, except per share data):


	Three months ended June 30,
	2013			2012
Numerator:
Net loss	$	(10,513	)	$	(10,275	)

Denominator:
Weighted-average shares of common stock outstanding		60,463			51,997
Weighted-average shares subject to repurchase		(2,163	)		(806	)

Shares used in per-share calculation — basic		58,300			51,191
Shares used in per-share calculation — diluted		58,300			51,191

Net loss per share — basic	$	(0.18	)	$	(0.20	)

Net loss per share — diluted	$	(0.18	)	$	(0.20	)

Fair Value Measurements (Tables)

3 Months Ended

Jun. 30, 2013

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Carried at Fair Value

The following table provides the assets carried at fair value, measured as of June 30, 2013 and March 31, 2013 (in thousands):


	Total Carrying Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
June 30, 2013:
Assets:
Cash equivalents	$	18,658	$	18,658	$	—	$	—
Liabilities:
Derivative liability	$	477	$	—	$	—	$	477
Warrants	$	3,216	$	—	$	—	$	3,216

	Total Carrying Value		Quoted Prices in Active Markets (Level 1)		Using Significant Other Observable Inputs (Level 2)		Using Significant Unobservable Inputs (Level 3)
March 31, 2013:
Assets:
Cash equivalents	$	18,649	$	18,649	$	—	$	—
Liabilities:
Derivative liability	$	529	$	—	$	—	$	529
Warrants	$	3,633	$	—	$	—	$	3,633

Schedule of Liabilities Measured at Fair Value

The table below reflects the activity for the Company’s major classes of liabilities measured at fair value for the period ended June 30, 2013 (in thousands).


	Derivative Liability			Warrants
April 1, 2013	$	529		$	3,633
Mark to market adjustment		(52	)		(417	)

Balance at June 30, 2013	$	477		$	3,216


	Derivative Liability			Warrants
April 1, 2012	$	—		$	—
Valuation of derivative liability		3,779			—
Warrant issuance with Senior Convertible Notes		—			7,018
Warrant issuance with Senior Secured Term Loan		—			380
Valuation of derivative liability attributable to modification		542			—
Mark to market adjustment		(3,792	)		(3,765	)

Balance at March 31, 2013	$	529		$	3,633

Accounts Receivable (Tables)

3 Months Ended

Jun. 30, 2013

Receivables [Abstract]

Schedule of Accounts Receivable

Accounts receivable at June 30, 2013 and March 31, 2013 consisted of the following (in thousands):


	June 30, 2013		March 31, 2013
Accounts receivable (billed)	$	9,225	$	17,222
Accounts receivable (unbilled)		1,863		1,642
Less: Allowance for doubtful accounts		—		—

Accounts receivable, net	$	11,088	$	18,864

Inventory (Tables)

3 Months Ended

Jun. 30, 2013

Inventory Disclosure [Abstract]

Schedule of Inventory

The components of inventory at June 30, 2013 and March 31, 2013 are as follows (in thousands):


	June 30, 2013		March 31, 2013
Raw materials	$	6,423	$	5,966
Work-in-process		3,730		3,427
Finished goods		17,914		21,655
Deferred program costs		2,685		2,425

Net inventory	$	30,752	$	33,473

Accounts Payable and Accrued Expenses (Tables)

3 Months Ended

Jun. 30, 2013

Payables And Accruals [Abstract]

Schedule of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consisted of the following (in thousands):


	June 30,		March 31,
	2013		2013
Accounts payable	$	4,174	$	7,146
Accrued miscellaneous expenses		9,419		9,142
Accrued VAT		1,517		809
Accrued outside services		2,744		2,251
Accrued subcontractor program costs		512		2,442
Accrued compensation		4,153		5,506
Income taxes payable		175		133
Accrued warranty		2,787		2,709

Total	$	25,481	$	30,138

Schedule of Product Warranty Activity

Product warranty activity was as follows (in thousands):


	Three months ended June 30,
	2013			2012
Balance at beginning of period	$	2,709		$	5,896
Accruals for warranties during the period		152			(167	)
Settlements during the period		(74	)		(229	)

Balance at end of period	$	2,787		$	5,500

Restructuring (Tables)

3 Months Ended

Jun. 30, 2013

Restructuring And Related Activities [Abstract]

Schedule of Restructuring Charges and Cash Payments

The following table presents restructuring charges and cash payments (in thousands):


	Severance pay and benefits			Facility exit costs			Total
Three months ended June 30, 2013
Accrued restructuring balance at April 1, 2013	$	199			—		$	199
Charges to operations		13			—			13
Cash payments		(136	)		—			(136	)

Accrued restructuring balance at June 30, 2013	$	76		$	—		$	76


Three months ended June 30, 2012
Accrued restructuring balance at April 1, 2012	$	680		$	294		$	974
Charges to operations		167			(39	)		128
Cash payments		(269	)		(255	)		(524	)

Accrued restructuring balance at June 30, 2012	$	578		$	—		$	578

Warrants and Derivative Liabilities (Tables)

3 Months Ended

Jun. 30, 2013

Schedule of Fair Value Assumptions Used to Calculate Value of Convertible Note Derivative Feature

Following is a summary of the key assumptions used to value the convertible notes derivative feature:


	June 30,
	2013
Fiscal Year 2013

Principal Outstanding (000’s)	$	14,389
Stock Price	$	2.64
Percentage Volume Condition Met		87.5	%
Expected Volatility		65.8	%
Risk Free Rate		0.21	%
Bond Yield		16.7	%
Recovery Rate		37.0	%
Redeemable		yes
Total Time (years)		1.26
Dilution Effect		yes
Fair Value	$	0.5 million
Fair Value as a Percent of Par		3.3	%


							Post- modification			Pre-modification
	March 31,			December 31,			December 20,			December 20,			September 30,			June 30,			April 4,
	2013			2012			2012			2012			2012			2012			2012
Fiscal Year 2012

Principal Outstanding (000’s)	$	15,380		$	20,944		$	20,944		$	24,617		$	24,191		$	25,278		$	25,000
Stock Price	$	2.67		$	2.62		$	2.95		$	2.95		$	4.15		$	4.68		$	3.97
Percentage Volume Condition Met		80.5	%		94.5	%		94.9	%		28.6	%		51.0	%		75.2	%		85.9	%
Expected Volatility		66.9	%		73.5	%		72.5	%		72.5	%		70.0	%		71.0	%		75.0	%
Risk Free Rate		0.20	%		0.23	%		0.25	%		0.25	%		0.23	%		0.33	%		0.44	%
Bond Yield		16.5	%		16.5	%		16.5	%		16.5	%		15.0	%		16.0	%		15.0	%
Recovery Rate		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%		30.0	%
Redeemable		yes			yes			yes			yes			yes			yes			yes
Total Time (years)		1.51			1.76			1.79			1.79			2.01			2.28			2.5
Dilution Effect		yes			yes			yes			yes			yes			yes			yes
Fair Value as a Percent of Par		3.4	%		4.9	%		7.1	%		3.9	%		11.4	%		17.9	%		15.1	%
Fair Value	$	0.5 million		$	1.0 million		$	1.5 million		$	0.9 million		$	2.8 million		$	4.5 million		$	3.8 million

Securities Purchase Agreement [Member]

Schedule of Fair Value of Warrants Using Black-Scholes Option Pricing Model

Following is a summary of the key assumptions used to calculate the fair value of the warrant:


	June 30, 2013
Fiscal Year 2013

Risk-free interest rate		1.13	%
Expected annual dividend yield		0.0	%
Expected volatility		71.9	%
Term (years)		4.27
Fair Value	$	3.0 million


	March 31,			December 31,			September 30,			June 30,			April 4,
	2013			2012			2012			2012			2012
Fiscal Year 2012

Risk-free interest rate		0.67	%		0.75	%		0.63	%		0.77	%		1.19	%
Expected annual dividend yield		0.0	%		0.0	%		0.0	%		0.0	%		0.0	%
Expected volatility		71.7	%		80.6	%		80.9	%		80.8	%		80.0	%
Term (years)		4.51			4.76			5.01			5.28			5.5
Fair Value	$	3.4 million		$	4.4 million		$	7.1 million		$	8.6 million		$	7.0 million

Loan and Security Agreement [Member]

Schedule of Fair Value of Warrants Using Black-Scholes Option Pricing Model

Following is a summary of the key assumptions used to calculate the fair value of the warrant:


	June 30,
	2013
Fiscal Year 2013

Risk-free interest rate		1.20	%
Expected annual dividend yield		—	%
Expected volatility		72.3	%
Term (years)		4.43
Fair Value	$	0.2 million


	March 31,			December 31,			September 30,			June 30,			June 5,
	2013			2012			2012			2012			2012
Fiscal Year 2012

Risk-free interest rate		0.70	%		0.75	%		0.64	%		0.80	%		0.77	%
Expected annual dividend yield		—	%		—	%		—	%		—	%		—	%
Expected volatility		72.01	%		80.14	%		81.18	%		80.32	%		79.99	%
Term (years)		4.68			4.93			5.18			5.44			5.5
Fair Value	$	0.2 million		$	0.2 million		$	0.4 million		$	0.5 million		$	0.4 million

Equity Investments (Tables)

3 Months Ended

Jun. 30, 2013

Tres Amigas [Member]

Schedule of Net Investment Activity

The net investment activity for the three months ended June 30, 2013 is as follows (in thousands):


Balance at April 1, 2013	$	2,853
Minority interest in net losses		(248	)

Balance at June 30, 2013	$	2,605

Blade Dynamics Ltd. [Member]

Schedule of Net Investment Activity

The net investment activity for the three months ended June 30, 2013 is as follows (in thousands):


Balance at April 1, 2013	$	4,611
Minority interest in net losses		—
Net foreign exchange rate impact		(69	)

Balance at June 30, 2013	$	4,680

Business Segments (Tables)

3 Months Ended

Jun. 30, 2013

Segment Reporting [Abstract]

Operating Results for Two Business Segments

The operating results for the two business segments are as follows (in thousands):


	Three months ended June 30,
	2013			2012
Revenues:
Wind	$	14,701		$	16,511
Grid		8,385			12,205

Total	$	23,086		$	28,716


	Three months ended June 30,
	2013			2012
Operating (loss) income:
Wind	$	(1,825	)	$	1,301
Grid		(4,869	)		(5,343	)
Unallocated corporate expenses		(2,156	)		(2,086	)

Total	$	(8,850	)	$	(6,128	)

Total Business Segments Assets

Total assets for the two business segments are as follows (in thousands):


	June 30, 2013		March 31, 2013
Wind	$	56,015	$	67,111
Grid		72,252		72,800
Corporate assets		65,926		76,843

Total	$	194,193	$	216,754

Schedule of Revenues by Major Customers

The following table sets forth customers who represented 10% or more of the Company’s total revenues for the three months ended June 30, 2013 and 2012:


	Three months ended
	June 30,
	2013			2012
Beijing JINGCHENG New Energy Co., Ltd.		35	%		19	%
INOX Wind Limited		15	%		15	%
Karara Mining Ltd		<1	%		15	%

Nature of the Business and Operations and Liquidity - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended		1 Months Ended	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Mar. 31, 2013	Mar. 31, 2012	Jul. 24, 2013 Subsequent Event [Member]	Sep. 30, 2013 Subsequent Event [Member]	Jul. 31, 2013 Subsequent Event [Member]	Apr. 04, 2012 Senior Convertible Debt [Member]	Jun. 05, 2012 Senior Secured Term Loan [Member]
Description Of Business [Line Items]
Accumulated deficit	$ (810,644,000)		$ (800,131,000)
Cash and cash equivalents	32,608,000	60,487,000	39,243,000	46,279,000
Net cash used in operating activities	(9,307,000)	(11,591,000)
Debt, face amount		35,000,000						25,000,000	10,000,000
Reduction in global workforce, percentage			57.00%		7.00%
Restructuring charge for severance and other costs						1,000,000
Interest rate percentage								7.00%
Amount of exchanged note converted							4,000,000
Reduction of principle from conversion of shares	$ 10,600,000

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 2,135	$ 1,994
Cost of Revenues [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	205	170
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	575	562
Selling, General and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,355	$ 1,262

Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted in period	314,765
Vesting period, in years	3 years
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 3.3
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)	1 year 10 months 24 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 4.6
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)	1 year 3 months 18 days
2007 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted in period	154,080
U.S. Treasury Rates [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation plans expired terms	5 years
U.S. Treasury Rates [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation plans expired terms	7 years

Stock-Based Compensation - Schedule of Weighted Average Assumptions used in Black-Scholes Valuation Model for Stock Options Granted (Detail)	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Expected volatility	74.60%	72.00%
Risk-free interest rate	1.70%	0.90%
Expected life (years)	5 years 10 months 24 days	5 years 10 months 24 days
Dividend yield	0.00%	0.00%

Computation of Net (Loss) Income Per Common Share - Additional Information (Detail) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Dilutive Securities Included And Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted EPS	6.1	6.3
Unvested Options [Member]
Dilutive Securities Included And Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted EPS	2.9	3.1
Warrants [Member]
Dilutive Securities Included And Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted EPS	3.2	3.2

Computation of Net (Loss) Income Per Common Share - Reconciliation of Numerators and Denominators of EPS Calculation (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Net loss	$ (10,513)	$ (10,275)
Weighted-average shares of common stock outstanding	60,463	51,997
Weighted-average shares subject to repurchase	(2,163)	(806)
Shares used in per-share calculation - basic	58,300	51,191
Shares used in per-share calculation - diluted	58,300	51,191
Net loss per share - basic	$ (0.18)	$ (0.20)
Net loss per share - diluted	$ (0.18)	$ (0.20)

Fair Value Measurements - Schedule of Assets and Liabilities Carried at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Apr. 04, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 18,658	$ 18,649
Derivative liability	477	529	1,000	2,800	4,500	3,800
Warrants	3,216	3,633
Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	18,658	18,649
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents
Derivative liability
Warrants
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	477	529
Warrants	$ 3,216	$ 3,633

Fair Value Measurements - Schedule of Liabilities Measured at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Derivative Liability [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning Balance	$ 477	$ 529
Valuation of derivative liability		3,779
Valuation of derivative liability attributable to modification		542
Mark to market adjustment	(52)	(3,792)
Ending Balance	477	529
Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning Balance	3,216	3,633
Warrant issuance with Senior Convertible Notes		7,018
Warrant issuance with Senior Secured Term Loan		380
Mark to market adjustment	(417)	(3,765)
Ending Balance	$ 3,216	$ 3,633

Accounts Receivable - Schedule of Accounts Receivable (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Receivables [Abstract]
Accounts receivable (billed)	$ 9,225	$ 17,222
Accounts receivable (unbilled)	1,863	1,642
Less: Allowance for doubtful accounts
Accounts receivable, net	$ 11,088	$ 18,864

Inventory - Schedule of Inventory (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 6,423	$ 5,966
Work-in-process	3,730	3,427
Finished goods	17,914	21,655
Deferred program costs	2,685	2,425
Net inventory	$ 30,752	$ 33,473

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Payables And Accruals [Abstract]
Accounts payable	$ 4,174	$ 7,146
Accrued miscellaneous expenses	9,419	9,142
Accrued VAT	1,517	809
Accrued outside services	2,744	2,251
Accrued subcontractor program costs	512	2,442
Accrued compensation	4,153	5,506
Income taxes payable	175	133
Accrued warranty	2,787	2,709
Total	$ 25,481	$ 30,138

Accounts Payable and Accrued Expenses - Schedule of Product Warranty Activity (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Payables And Accruals [Abstract]
Balance at beginning of period	$ 2,709	$ 5,896
Accruals for warranties during the period	152	(167)
Settlements during the period	(74)	(229)
Balance at end of period	$ 2,787	$ 5,500

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Jun. 30, 2013	Jun. 30, 2012
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 90,000	$ (836,000)
Foreign income tax benefit		$ 900,000

Restructuring - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Mar. 31, 2013
Restructuring Cost and Reserve [Line Items]
Reduction in global workforce, percentage			57.00%
Restructuring costs	$ 13	$ 128
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 100	$ 100

Restructuring - Schedule of Restructuring Charges and Cash Payments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Restructuring Cost and Reserve [Line Items]
Accrued restructuring balance	$ 199	$ 974
Charges to operations	13	128
Cash payments	(136)	(524)
Accrued restructuring balance	76	578
Severance Pay and Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring balance	199	680
Charges to operations	13	167
Cash payments	(136)	(269)
Accrued restructuring balance	76	578
Facility Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring balance		294
Charges to operations		(39)
Cash payments		(255)
Accrued restructuring balance

Debt - Additional Information (Detail) (USD $)	3 Months Ended				1 Months Ended	3 Months Ended		12 Months Ended	1 Months Ended		3 Months Ended			0 Months Ended		1 Months Ended	0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended
Debt - Additional Information (Detail) (USD $)	Jun. 30, 2013	Jun. 30, 2012	Mar. 31, 2013	Apr. 30, 2013 New Unsecured Senior Convertible Note [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Jun. 30, 2013 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Dec. 03, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Mar. 31, 2013 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Minimum [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Maximum [Member]	Jun. 30, 2013 Senior Convertible Debt [Member]	Jun. 30, 2012 Senior Convertible Debt [Member]	Apr. 04, 2012 Senior Convertible Debt [Member]	Apr. 04, 2012 Senior Convertible Debt [Member] Capital Ventures International [Member]	Apr. 04, 2010 Senior Convertible Debt [Member] Capital Ventures International [Member]	Dec. 31, 2012 Senior Convertible Debt [Member] Capital Ventures International [Member]	Jun. 05, 2012 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]	Jun. 30, 2013 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]	Jun. 30, 2012 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]	Mar. 31, 2013 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]	Jun. 05, 2012 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member] Minimum [Member]
Debt Instrument [Line Items]
Interest rate percentage				7.00%									7.00%
Net proceeds after fees and expenses of purchase agreement														$ 23,200,000
Conversion price									$ 3.19	$ 4.85					$ 4.85
Premium over closing price, percentage															20.00%
Period before first installment payment														4 months
Shares registered for resale														10,262,311
Derivative liability of note	3,693,000		4,162,000		1,500,000									3,800,000
Number of shares received from warrants received to purchase common stock														3,094,060			139,276
Strike price per share														$ 5.45			$ 3.59
Fair value of warrants at issuance								25,000,000						7,000,000			400,000
Legal and origination costs								1,800,000												300,000
Amendment covenant description					Allow the Company to convert, subject to the satisfaction of certain conditions set forth in the Exchanged Note, (a) at least $2.5 million of the approximately $5.3 million installment amount payable with respect to the January 2013 installment date (including approximately $4.2 million of deferred installment amounts from the period September 4, 2012 to December 3, 2012) into shares of the Company's common stock (on December 21, 2012 the Company converted $3.8 million in deferred installment amount principal and interest and issued 1,715,443 shares of common stock), and (b) the balance of the January 2013 installment amount in equal amounts on each of the February and March 2013 installment dates; Reduce the price failure equity condition with respect to a particular date of determination from $2.50 to $1.00;Reduce the aggregate daily dollar trading volume equity condition required for at least 25 of the 30 consecutive trading days immediately preceding a date of determination from $1,500,000 to $850,000 per trading day. In addition, if the aggregate daily dollar trading volume is between $50,000 and $850,000, the Company may still convert into common stock a portion of an installment amount payable with respect to an installment date equal to the quotient of (x) the aggregate daily dollar trading volume, divided by (y) $850,000;Increase CVI's beneficial ownership limitation under the Exchanged Note from 4.99% to 9.99%; andReduce the conversion price, from $4.85 per share of the Company's common stock to $3.19 per share of the Company's common stock, subject to certain price-based and other anti-dilution adjustments.
Portion of installment payment to be converted									2,500,000
Installment amount of note payable					5,300,000
Deferred installment payments of note payable							4,200,000
Convertible amount of installment payment	1,832,000	1,016,000			3,800,000
Number of shares issued for converted payment					1,715,443
Price failure equity condition									$ 1.00	$ 2.50
Aggregate daily dollar trading volume					850,000				50,000	850,000						1,500,000
Minimum number of consecutive trading days for reducing daily dollar trading					25 days
Number of trading days immediately preceding date of determination					30 days
Beneficial ownership limitation percentage									4.99%	9.99%
Increase in derivative liability					500,000	500,000
Total debt discount being amortized into interest expense					13,100,000
Non-cash interest expense amortization of debt discount	1,700,000	2,300,000									1,500,000	2,200,000						100,000	100,000
Percentage of stock discount	85.00%
Non-cash interest expense issuing stock at discount	100,000
Number of trading days for valuation of shares	10 days
Borrowed amount																	10,000,000
Proceeds from the issuance of debt, net of expenses																	9,700,000
Interest rate on loan																	11.00%
Prime rate																					3.75%
End of term fee																				500,000
Interest expense	2,100,000	2,700,000																		1,200,000
Covenant, unrestricted cash balance requirement																		$ 10,000,000

Warrants and Derivative Liabilities - Additional Information (Detail) (USD $)	3 Months Ended							0 Months Ended		1 Months Ended	3 Months Ended	1 Months Ended		0 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Convertible Bond [Member]	Jun. 30, 2012 Convertible Bond [Member]	Jun. 30, 2013 Capital Ventures International [Member]	Jun. 30, 2012 Capital Ventures International [Member]	Jun. 30, 2012 Hercules Technology Growth Capital [Member]	Apr. 04, 2012 Senior Convertible Debt [Member] Capital Ventures International [Member]	Apr. 04, 2010 Senior Convertible Debt [Member] Capital Ventures International [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Jun. 30, 2013 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Minimum [Member]	Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Maximum [Member]	Jun. 05, 2012 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]
Derivative [Line Items]
Number of shares received from warrants received to purchase common stock								3,094,060						139,276
Warrant exercise, waiting period					6 months
Warrant exercise period					5 years
Exercise price								$ 5.45						$ 3.59
Beneficial ownership limitation percentage												4.99%	9.99%
Required notification period					61 days
Gain (loss) in change of fair value of derivative instruments and warrants	$ 469,000	$ (2,388,000)	$ 100,000	$ (700,000)	$ 400,000	$ (1,600,000)	$ (100,000)
Conversion price									$ 4.85			$ 3.19	$ 4.85
Increase in derivative liability										$ 500,000	$ 500,000
Convertible debt instrument redemption waiting period	1 year
Convertible debt instrument contractual term	30 months

Warrants and Derivative Liabilities - Schedule of Fair Value of Warrants Using Black-Scholes Option Pricing Model (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended					0 Months Ended	3 Months Ended					0 Months Ended	3 Months Ended
	Apr. 04, 2012	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Apr. 04, 2012 Securities Purchase Agreement [Member]	Jun. 30, 2013 Securities Purchase Agreement [Member]	Mar. 31, 2013 Securities Purchase Agreement [Member]	Dec. 31, 2012 Securities Purchase Agreement [Member]	Sep. 30, 2012 Securities Purchase Agreement [Member]	Jun. 30, 2012 Securities Purchase Agreement [Member]	Jun. 05, 2012 Loan and Security Agreement [Member]	Jun. 30, 2013 Loan and Security Agreement [Member]	Mar. 31, 2013 Loan and Security Agreement [Member]	Dec. 31, 2012 Loan and Security Agreement [Member]	Sep. 30, 2012 Loan and Security Agreement [Member]	Jun. 30, 2012 Loan and Security Agreement [Member]
Derivative [Line Items]
Risk-free interest rate	0.44%	0.21%	0.20%	0.23%	0.23%	0.33%	1.19%	1.13%	0.67%	0.75%	0.63%	0.77%	0.77%	1.20%	0.70%	0.75%	0.64%	0.80%
Expected annual dividend yield	15.00%	16.70%	16.50%	16.50%	15.00%	16.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
Expected volatility	75.00%	65.80%	66.90%	73.50%	70.00%	71.00%	80.00%	71.90%	71.70%	80.60%	80.90%	80.80%	79.99%	72.30%	72.01%	80.14%	81.18%	80.32%
Term (years)	2 years 6 months	1 year 3 months 4 days	1 year 6 months 4 days	1 year 9 months 4 days	2 years 4 days	2 years 3 months 11 days	5 years 6 months	4 years 3 months 7 days	4 years 6 months 4 days	4 years 9 months 4 days	5 years 4 days	5 years 3 months 11 days	5 years 6 months	4 years 5 months 5 days	4 years 8 months 5 days	4 years 11 months 5 days	5 years 2 months 5 days	5 years 5 months 9 days
Fair Value							$ 7.0	$ 3.0	$ 3.4	$ 4.4	$ 7.1	$ 8.6	$ 0.4	$ 0.2	$ 0.2	$ 0.2	$ 0.4	$ 0.5

Warrants and Derivative Liabilities - Schedule of Fair Value Assumptions Used to Calculate Value of Convertible Note Derivative Feature (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended					1 Months Ended
	Apr. 04, 2012	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 20, 2012 Post-Modification [Member]	Dec. 20, 2012 Pre-Modification [Member]
Principal Outstanding (000's)	$ 25,000	$ 14,389	$ 15,380	$ 20,944	$ 24,191	$ 25,278	$ 20,944	$ 24,617
Stock Price	$ 3.97	$ 2.64	$ 2.67	$ 2.62	$ 4.15	$ 4.68	$ 2.95	$ 2.95
Percentage Volume Condition Met	85.90%	87.50%	80.50%	94.50%	51.00%	75.20%	94.90%	28.60%
Expected volatility	75.00%	65.80%	66.90%	73.50%	70.00%	71.00%	72.50%	72.50%
Risk Free Rate	0.44%	0.21%	0.20%	0.23%	0.23%	0.33%	0.25%	0.25%
Bond Yield	15.00%	16.70%	16.50%	16.50%	15.00%	16.00%	16.50%	16.50%
Recovery Rate	30.00%	37.00%	30.00%	30.00%	30.00%	30.00%	30.00%	30.00%
Redeemable	yes	yes	yes	yes	yes	yes	yes	yes
Total Time (years)	2 years 6 months	1 year 3 months 4 days	1 year 6 months 4 days	1 year 9 months 4 days	2 years 4 days	2 years 3 months 11 days	1 year 9 months 15 days	1 year 9 months 15 days
Dilution Effect	yes	yes	yes	yes	yes	yes	yes	yes
Fair Value	$ 3,800	$ 477	$ 529	$ 1,000	$ 2,800	$ 4,500	$ 1,500	$ 900
Fair Value as a Percent of Par	15.10%	3.30%	3.40%	4.90%	11.40%	17.90%	7.10%	3.90%

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended	0 Months Ended	1 Months Ended		3 Months Ended			0 Months Ended				1 Months Ended				0 Months Ended		12 Months Ended		0 Months Ended
	May 17, 2013 USD ($)	Jul. 05, 2011 Claim	Jun. 17, 2011 Claim	May 12, 2011 Employees Claim	Jun. 30, 2013 USD ($) Bonds	Jun. 30, 2013 EUR (€)	Mar. 31, 2013 USD ($)	Oct. 17, 2011 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Oct. 17, 2011 Sinovel Wind Group Co. Ltd. [Member] CNY	Oct. 08, 2011 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Oct. 08, 2011 Sinovel Wind Group Co. Ltd. [Member] CNY	Feb. 27, 2012 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Feb. 27, 2012 Sinovel Wind Group Co. Ltd. [Member] CNY	Dec. 22, 2011 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Dec. 22, 2011 Sinovel Wind Group Co. Ltd. [Member] CNY	Sep. 13, 2011 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Sep. 13, 2011 Sinovel Wind Group Co. Ltd. [Member] CNY	Mar. 31, 2011 Sinovel Wind Group Co. Ltd. [Member] USD ($)	Mar. 31, 2011 Sinovel Wind Group Co. Ltd. [Member] CNY	Sep. 16, 2011 Dalian Guotong Electric Co. Ltd. [Member] USD ($)	Sep. 16, 2011 Dalian Guotong Electric Co. Ltd. [Member] CNY	May 12, 2011 Ghodawat Energy Pvt Ltd [Member] USD ($)	May 12, 2011 Ghodawat Energy Pvt Ltd [Member] EUR (€)
Commitments And Contingencies [Line Items]
Adverse purchase commitments					$ 1,179,000		$ 1,440,000
Adjusted accrual for adverse purchase commitments					300,000
Number of putative securities complaints			4	7
Number of officers putative securities filed against				2
Number of complaints additionally asserted claims against the underwriters				1
Loss contingency	1,800,000
Number of claims consolidated		3
Sought compensation amount								157,000,000	1,000,000,000	58,000,000	370,000,000	17,000,000	105,000,000	190,000,000	1,200,000,000			76,000,000	485,000,000			24,000,000	18,000,000
Value of the undelivered components																		720,000,000	4,600,000,000
Damages claimed for unauthorized use of software																6,000,000	38,000,000
Monetary damages for trade secret infringement																453,000,000	2,900,000,000
Monetary losses from copyright infringement																				200,000	1,200,000
Counterclaims under License Agreement																						9,000,000	6,000,000
Restricted cash included in current assets					824,000		6,136,000
Restricted cash					6,098,000		4,820,000
Number of performance bonds in support of customer contracts					1
Value of performance bond					200,000
Debt instrument maturity date					Mar. 31, 2014
Line of credit outstanding					$ 3,500,000	€ 2,700,000

Equity Investments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				3 Months Ended
	Jun. 30, 2013 Tres Amigas [Member]	May 20, 2011 Tres Amigas [Member]	Jan. 06, 2011 Tres Amigas [Member]	Oct. 09, 2009 Tres Amigas [Member] Item	Jun. 30, 2013 Blade Dynamics Ltd. [Member]	Aug. 12, 2010 Blade Dynamics Ltd. [Member]
Schedule of Equity Method Investments [Line Items]
Acquisition date	Oct. 09, 2009				Aug. 12, 2010
Number of commonly interconnected power grids				3
Equity method investment, aggregate cost				$ 1.8
Equity method investment in cash				0.8		8.0
Equity method investment in common stock				1.0
Cash consideration for increase in minority position		$ 1.8	$ 1.8
Equity method investment ownership percentage	26.00%				19.00%

Equity Investments - Schedule of Net Investment Activity (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Net foreign exchange rate impact	$ (35)	$ (1,168)
Tres Amigas [Member]
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Beginning balance	2,853
Minority interest in net losses	(248)
Ending balance	2,605
Blade Dynamics Ltd. [Member]
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Beginning balance	4,611
Minority interest in net losses
Net foreign exchange rate impact	(69)
Ending balance	$ 4,680

Business Segments - Operating Results for Two Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 23,086	$ 28,716
Operating (loss) income	(8,850)	(6,128)
Operating Segments [Member] \| Wind [Member]
Segment Reporting Information [Line Items]
Revenues	14,701	16,511
Operating (loss) income	(1,825)	1,301
Operating Segments [Member] \| Grid [Member]
Segment Reporting Information [Line Items]
Revenues	8,385	12,205
Operating (loss) income	(4,869)	(5,343)
Unallocated Corporate Expenses [Member]
Segment Reporting Information [Line Items]
Operating (loss) income	$ (2,156)	$ (2,086)

Business Segments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013 Segment	Jun. 30, 2012
Segment Reporting [Abstract]
Number of reportable business segments	2
Stock-based compensation expense	$ 2,135	$ 1,994

Business Segments - Total Business Segments Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 194,193	$ 216,754
Operating Segments [Member] \| Wind [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	56,015	67,111
Operating Segments [Member] \| Grid [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	72,252	72,800
Unallocated Corporate Expenses [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 65,926	$ 76,843

Business Segments - Schedule of Revenues by Major Customers (Detail) (Sales [Member])	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Beijing JINGCHENG New Energy Co., Ltd. [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue percentage	35.00%	19.00%
INOX Wind Limited. [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue percentage	15.00%	15.00%
Karara Mining Ltd. [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue percentage		15.00%
Karara Mining Ltd. [Member] \| Maximum [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Revenue percentage	1.00%

Subsequent Events - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended	1 Months Ended	3 Months Ended
	Mar. 31, 2013	Jul. 24, 2013 Subsequent Event [Member]	Sep. 30, 2013 Subsequent Event [Member]
Subsequent Event [Line Items]
Company reduced its workforce	57.00%	7.00%
Company expects to record a restructuring charge for severance and other costs			$ 1.0

Fair Value Measurements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013
Fair Value Disclosures [Abstract]
Amount of additional convertible notes and warrants	$ 15.0

Accounts Payable and Accrued Expenses - Additional Information (Detail)	3 Months Ended
	Jun. 30, 2013
Minimum [Member]
Product Warranty Accrual [Line Items]
Warranty period	1 year
Maximum [Member]
Product Warranty Accrual [Line Items]
Warranty period	3 years