Represents the number of additional shares to be issued.

No definition available.

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid in shares.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of currency on hand as well as demand deposits with banks or financial institutions, and marketable securities.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate value of a supply agreement.

+ References

No definition available.

+ Details

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- Definition

The amount of letters of credit to be received for goods and services to be continued under the supply commitment.

+ References

No definition available.

+ Details

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- Definition

Represents the extension period under a supply commitment.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The amount of letters of credit received during the period for supply commitment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Balance Type:	na
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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

- Definition

The cash inflow from the additional capital contribution to the entity.

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Balance Type:	debit
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Balance Type:	credit
Period Type:	instant

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of new stock issued during the period.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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Note 1 - Nature of the Business and Operations and Liquidity (Details Textual) $ / shares in Units, $ in Thousands, € in Millions				1 Months Ended	7 Months Ended	9 Months Ended
	Oct. 26, 2020 USD ($) $ / shares shares	Oct. 01, 2020 USD ($) $ / shares shares	Sep. 02, 2020 EUR (€)	Dec. 31, 2015 USD ($)	Oct. 26, 2019 USD ($)	Dec. 31, 2020 USD ($)	Sep. 11, 2020 EUR (€)	May 29, 2020 EUR (€)	Mar. 31, 2020 USD ($)
Retained Earnings (Accumulated Deficit), Ending Balance						$ (993,697)			$ (978,635)
Cash, Cash Equivalents, and Marketable Securities						78,100
Net Cash Provided by (Used in) Operating Activities, Total					$ (17,779)	(4,871)
Payments to Acquire Businesses, Gross						26,000
Proceeds from Issuance of Common Stock						$ 51,477
Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares) \| shares	3,670,000
Shares Issued, Price Per Share (in dollars per share) \| $ / shares	$ 15
Proceeds from Issuance of Common Stock	$ 51,500
Additional Shares to be Issued (in shares) \| shares	550,500
Northeast Power Systems, Inc (NEPSI) [Member]
Payments to Acquire Businesses, Gross		$ 26,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares) \| shares		873,657
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High, Number of Shares (in shares) \| shares		1,000,000
Shares Issued, Price Per Share (in dollars per share) \| $ / shares		$ 14.23
Northeast Power Systems, Inc (NEPSI) [Member] \| Restricted Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares) \| shares		873,657
Inox Wind Limited [Member]
Supply Agreement, Aggregate Value				$ 210,000
Supply Commitment, Extension Period (Year)				3 years
Supply Commitment, Default, Letters of Credit to be Received \| €							€ 4.7	€ 6.0
Supply Commitment, Letters of Credit Received \| €			€ 1.3
Certificates of Deposit [Member] \| Minimum [Member]
Debt Securities, Available-for-sale, Term (Month)						90 days
Certificates of Deposit [Member] \| Maximum [Member]
Debt Securities, Available-for-sale, Term (Month)						270 days