v2.4.0.6
Document And Entity Information
6 Months Ended
Sep. 30, 2011
Nov. 01, 2011
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 30, 2011  
Document Fiscal Year Focus 2012  
Document Fiscal Period Focus Q2  
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   51,421,143