Note 11 - Accounts Payable and Accrued Expenses (Details Textual)	6 Months Ended
Sep. 30, 2019
Minimum [Member]
Extended Warranty Trigger Period	1 year
Maximum [Member]
Extended Warranty Trigger Period	3 years

The period in which customers may extend their warranty for an additional term.

No definition available.

Name:	amsc_ExtendedWarrantyTriggerPeriod
Namespace Prefix:	amsc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration