Class of Warrant or Right, Number of Warrants to Purchase One Share of Stock

No definition available.

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Period Type:	instant

- Definition

Gain (loss) in change of fair value of derivative instruments and warrants.

+ References

No definition available.

+ Details

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- Definition

Number of warrants issued to purchase common stock.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of common units issued of limited liability company (LLC).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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Period Type:	instant

- 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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability exceeding amount recognized at acquisition date. Includes, but is not limited to, measurement period adjustment and less amount paid soon after acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (ee)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3367-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=amsc_BusinessCombinationContingentConsiderationMember
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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=amsc_CapitalVenturesInternationalMember
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- Details

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- Details

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- Details

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- Details

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Warrants and Derivative Liabilities - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 05, 2018	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Dec. 19, 2014	Nov. 13, 2014	Apr. 04, 2012
Derivative [Line Items]
Change in fair value of derivatives and warrants		$ 706	$ 1,304	$ (228)
Hercules warrants
Derivative [Line Items]
Change in fair value of derivatives and warrants			100	100
November 2014 warrant
Derivative [Line Items]
Change in fair value of derivatives and warrants		700	$ 1,400	$ (100)
Common stock units offered (in shares)						909,090
Warrant 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
Acquisition contingent consideration
Derivative [Line Items]
Change in fair value of derivatives and warrants		$ (100)
Senior convertible debt \| Capital Ventures International \| Original warrants
Derivative [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)							309,406
Term debt \| Hercules warrants \| Hercules Technology Growth Capital
Derivative [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)					58,823
Exercise price (in dollars per share)					$ 7.85
Infinia Technology Corporation (ITC)
Derivative [Line Items]
Make Whole Payment	$ 700