XML 75 R64.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Warrants and Derivative Liabilities - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 19, 2014 | Jun. 30, 2018 | Jun. 30, 2017 | Mar. 31, 2018 | Nov. 13, 2014
Derivative [Line Items] |  |  |  |  |
Change in fair value of warrants and contingent consideration |  | $ (464) | $ 925 |  |
November 2014 Warrant |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Warrants expiration date |  | Nov. 13, 2019 |  |  |
Common stock units offered (in shares) |  |  |  |  | 909,090
Warrants to purchase one share of common stock (in shares) |  |  |  |  | 0.9
Number of warrants issued to purchase common stock (in shares) |  |  |  |  | 818,181
Sale of stock, price per share (in dollars per share) |  |  |  |  | $ 7.81
Change in fair value of warrants and contingent consideration |  | $ (500) | $ 900 |  |
Senior secured loan | Hercules Technology Growth Capital | First Warrant |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of shares received from warrants received to purchase common stock (in shares) |  | 13,927 |  |  |
Senior secured loan | Hercules Technology Growth Capital | Second Warrant |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of shares received from warrants received to purchase common stock (in shares) |  | 25,641 |  |  |
Senior secured loan | Hercules Technology Growth Capital | Hercules Warrants |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of shares received from warrants received to purchase common stock (in shares) | 58,823 |  |  |  |
Warrant exercise price (in dollars per share) |  | $ 7.85 |  |  |
Warrants expiration date |  | Jun. 30, 2020 |  |  |
Warrant fair value |  | $ 100 |  | $ 100 |

X
- Definition Class of Warrant or Right, Number of Warrants to Purchase One Share of Stock + References No definition available. + Details
Name: | amsc_ClassOfWarrantOrRightNumberOfWarrantsToPurchaseOneShareOfStock
Namespace Prefix: | amsc_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Gain (loss) in change of fair value of derivative instruments and warrants. + References No definition available. + Details
Name: | amsc_GainLossInChangeOfFairValueOfDerivativeInstrumentsAndWarrants
Namespace Prefix: | amsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of warrants issued to purchase common stock. + References No definition available. + Details
Name: | amsc_NumberOfWarrantsIssuedToPurchaseCommonStock
Namespace Prefix: | amsc_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Purchase commitment issuance of warrants shares of common stock. + References No definition available. + Details
Name: | amsc_PurchaseCommitmentIssuanceOfWarrantsSharesOfCommonStock
Namespace Prefix: | amsc_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Expiration date of warrants held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column A + Details
Name: | invest_InvestmentWarrantsExpirationDate
Namespace Prefix: | invest_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of common units issued of limited liability company (LLC). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055 + Details
Name: | us-gaap_CommonUnitIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. + References No definition available. + Details
Name: | us-gaap_SaleOfStockPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=amsc_NovemberTwoThousandFourteenWarrantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=amsc_HerculesTechnologyGrowthCapitalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=amsc_FirstWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=amsc_SecondWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=amsc_HerculesWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |