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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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 ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Subsidiary, Sale of Stock [Line Items]
Long-term debt	$ 506,453		$ 506,453		$ 390,899
Non-recourse debt, non-current	$ 386,743		$ 386,743		$ 270,053
Sales Revenue, Net \| Customer Concentration Risk \| Customer One
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage	31.00%		36.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Two
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage	26.00%		14.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Three
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage	12.00%
Accounts Receivable \| Customer Concentration Risk \| SK Engineering & Construction Co., Ltd.
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage			47.00%		56.00%
Accounts Receivable \| Customer Concentration Risk \| RAD Bloom Project LLC
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage			29.00%		0.00%
Asia Pacific \| Sales Revenue, Net \| Geographic Concentration Risk
Subsidiary, Sale of Stock [Line Items]
Concentration risk, percentage	34.00%	30.00%	39.00%	33.00%
Recourse debt
Subsidiary, Sale of Stock [Line Items]
Long-term debt	$ 290,670		$ 290,670		$ 168,008
Non-recourse debt, non-current	$ 288,650		$ 288,650		$ 168,008