For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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.

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Nature of Business, Liquidity and Basis of Presentation - (Additional Information) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 23, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Nov. 30, 2023
Subsidiary, Sale of Stock [Line Items]
Long-term debt		$ 504,196		$ 504,196		$ 390,899
Non-recourse debt, non-current		$ 490,380		$ 490,380		$ 270,053
Subsequent Event
Subsidiary, Sale of Stock [Line Items]
Shares sold in offering (in shares)	10,000
Offering price per share (in dollars per share)	$ 25.50						$ 23.00
Total Purchase Price	$ 255,000
Subsequent Event \| Series A preferred
Subsidiary, Sale of Stock [Line Items]
Preferred stock, par or stated (in dollars per share)	$ 0.0001
Sales Revenue, Net \| Customer Concentration Risk \| Customer One
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage		35.00%		37.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Two
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage				12.00%
Accounts Receivable \| Customer Concentration Risk \| SK Ecoplant
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage				22.00%		56.00%
Accounts Receivable \| Customer Concentration Risk \| RAD Bloom Project LLC
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage				16.00%		0.00%
Accounts Receivable \| Customer Concentration Risk \| Bronx Community Clean Energy Project
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage				18.00%		0.00%
Asia Pacific \| Sales Revenue, Net \| Geographic Concentration Risk
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage		36.00%	24.00%	38.00%	30.00%
Recourse debt
Subsidiary, Sale of Stock [Line Items]
Long-term debt		$ 291,250		$ 291,250		$ 168,008
Non-recourse debt, non-current		$ 285,216		$ 285,216		$ 168,008