XML 114 R52.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Warrants and Derivative Liabilities - Additional Information (Detail) (USD $) | 3 Months Ended | 0 Months Ended |  | 1 Months Ended | 3 Months Ended | 1 Months Ended | 0 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 Convertible Bond [Member] | Jun. 30, 2012 Convertible Bond [Member] | Jun. 30, 2013 Capital Ventures International [Member] | Jun. 30, 2012 Capital Ventures International [Member] | Jun. 30, 2012 Hercules Technology Growth Capital [Member] | Apr. 04, 2012 Senior Convertible Debt [Member] Capital Ventures International [Member] | Apr. 04, 2010 Senior Convertible Debt [Member] Capital Ventures International [Member] | Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] | Jun. 30, 2013 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] | Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Minimum [Member] | Dec. 31, 2012 New Unsecured Senior Convertible Note [Member] Capital Ventures International [Member] Maximum [Member] | Jun. 05, 2012 Senior Secured Term Loan [Member] Hercules Technology Growth Capital [Member]
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares received from warrants received to purchase common stock |  |  |  |  |  |  |  | 3,094,060 |  |  |  |  |  | 139,276
Warrant exercise, waiting period |  |  |  |  | 6 months |  |  |  |  |  |  |  |  |
Warrant exercise period |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Exercise price |  |  |  |  |  |  |  | $ 5.45 |  |  |  |  |  | $ 3.59
Beneficial ownership limitation percentage |  |  |  |  |  |  |  |  |  |  |  | 4.99% | 9.99% |
Required notification period |  |  |  |  | 61 days |  |  |  |  |  |  |  |  |
Gain (loss) in change of fair value of derivative instruments and warrants | $ 469,000 | $ (2,388,000) | $ 100,000 | $ (700,000) | $ 400,000 | $ (1,600,000) | $ (100,000) |  |  |  |  |  |  |
Conversion price |  |  |  |  |  |  |  |  | $ 4.85 |  |  | $ 3.19 | $ 4.85 |
Increase in derivative liability |  |  |  |  |  |  |  |  |  | $ 500,000 | $ 500,000 |  |  |
Convertible debt instrument redemption waiting period | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible debt instrument contractual term | 30 months |  |  |  |  |  |  |  |  |  |  |  |  |

X
- Definition Beneficial ownership limitation percentage. + References No definition available. + Details
Name: | amsc_BeneficialOwnershipLimitationPercentage
Namespace Prefix: | amsc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Convertible debt instrument contractual term. + References No definition available. + Details
Name: | amsc_ConvertibleDebtInstrumentContractualTerm
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Convertible debt instrument redemption waiting period. + References No definition available. + Details
Name: | amsc_ConvertibleDebtInstrumentRedemptionWaitingPeriod
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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 Ownership percentage notification period requirement. + References No definition available. + Details
Name: | amsc_OwnershipPercentageNotificationPeriodRequirement
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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 Warrant exercise period. + References No definition available. + Details
Name: | amsc_WarrantExercisePeriod
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Warrant exercise waiting period. + References No definition available. + Details
Name: | amsc_WarrantExerciseWaitingPeriod
Namespace Prefix: | amsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Exercise price of the warrants. + 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_InvestmentWarrantsExercisePrice
Namespace Prefix: | invest_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
Name: | us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of decrease in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
Name: | us-gaap_DerivativeLossOnDerivative
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration