XML 49 R39.htm IDEA: XBRL DOCUMENT  v2.3.0.11

Product Warranty (Details) (USD $) In Thousands	3 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Balance at beginning of period	$ 7,907	$ 6,431
Accruals for warranties during the period	(405)	2,305
Settlements during the period	(168)	(2,361)
Balance at end of period	$ 7,334	$ 6,375
Minimum [Member]
Warranty period, in years	one
Maximum [Member]
Warranty period, in years	three

X

- Definition

Warranty period

+ Details

Name:	amsc_WarrantyPeriod
Namespace Prefix:	amsc
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 15
-Subparagraph 5
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10

+ Details

Name:	us-gaap_ProductWarrantyAccrual
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Represents the aggregate increase (decrease) in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).

+ Details

Name:	us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ Details

Name:	us-gaap_ProductWarrantyAccrualWarrantiesIssued
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration