v3.4.0.3
Document and Entity Information - USD ($)
$ in Millions
12 Months Ended
Mar. 31, 2016
May. 25, 2016
Sep. 30, 2015
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Mar. 31, 2016    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Entity Registrant Name AMERICAN SUPERCONDUCTOR CORP /DE/    
Trading Symbol AMSC    
Entity Central Index Key 0000880807    
Current Fiscal Year End Date --03-31    
Entity Filer Category Accelerated Filer    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Common Stock, Shares Outstanding   14,045,836  
Entity Public Float     $ 50.2