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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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

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

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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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	6 Months Ended
	Oct. 26, 2020 USD ($) $ / shares shares	Oct. 01, 2020 USD ($) shares	Sep. 02, 2020 EUR (€)	Dec. 31, 2015 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 11, 2020 EUR (€)	May 29, 2020 EUR (€)	Mar. 31, 2020 USD ($)
Retained Earnings (Accumulated Deficit), Ending Balance					$ (985,764)				$ (978,635)
Cash, Cash Equivalents, and Marketable Securities					51,400
Net Cash Provided by (Used in) Operating Activities, Total					$ (6,553)	$ (10,485)
Subsequent Event [Member] \| 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	$ 51,400
Additional Shares to be Issued (in shares) \| shares	550,500
Northeast Power Systems, Inc (NEPSI) [Member] \| Subsequent Event [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, Consideration Transferred, Equity Interests Issued and Issuable		$ 1,000,000,000
Northeast Power Systems, Inc (NEPSI) [Member] \| Subsequent Event [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)					180 days
Certificates of Deposit [Member] \| Maximum [Member]
Debt Securities, Available-for-sale, Term (Month)					330 days