XML 80 R68.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Commitments and Contingencies - Additional Information (Detail) $ in Thousands | May 06, 2019 USD ($) | Jul. 04, 2018 USD ($) | Jul. 03, 2018 USD ($) installment | Sep. 30, 2018 USD ($) | Mar. 31, 2018 USD ($)
--- | --- | --- | --- | --- | ---
Commitments And Contingencies [Line Items] |  |  |  |  |
Restricted cash included in long-term assets |  |  |  | $ 165 | $ 165
Sinovel Wind Group Co. Ltd. |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |
Proceeds from settlement |  |  | $ 57,500 |  |
Number of installments | installment |  |  | 2 |  |
Settlement, amount awarded |  | $ 32,500 |  |  |
Payment period |  |  | 10 months |  |
Forecast | Sinovel Wind Group Co. Ltd. |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |
Settlement, amount awarded | $ 25,000 |  |  |  |

X
- Definition Commitments and contingencies. + References No definition available. + Details
Name: | amsc_CommitmentsAndContingenciesLineItems
Namespace Prefix: | amsc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Litigation Settlement, Number Of Installments + References No definition available. + Details
Name: | amsc_LitigationSettlementNumberOfInstallments
Namespace Prefix: | amsc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Litigation Settlement, Payment Period + References No definition available. + Details
Name: | amsc_LitigationSettlementPaymentPeriod
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Cash received for the settlement of litigation during the current period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 + Details
Name: | us-gaap_ProceedsFromLegalSettlements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(17)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 305 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84242212&loc=d3e2352-115587 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3044-108585 + Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_LitigationCaseAxis=amsc_SinovelWindGroupCoLtdMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |