Outstanding Loans and Security Agreements - Recourse Debt Facilities (Additional Information) (Details)		1 Months Ended	3 Months Ended		9 Months Ended
		Aug. 31, 2020 USD ($) $ / shares	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jan. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)	May 01, 2020 USD ($)
Debt Instrument [Line Items]
Long-term debt, current maturities			$ 13,816,000		$ 13,816,000			$ 120,846,000
Long-term debt, gross			516,037,000		516,037,000			527,054,000
Accumulated deficit			(3,229,752,000)		(3,229,752,000)			(3,103,937,000)
Decrease in additional paid-in capital			3,183,101,000		3,183,101,000			3,182,753,000
Non-recourse long term debt, non-current	[1]		205,164,000		205,164,000			$ 102,045,000
Contractual interest expense			$ 14,514,000	$ 19,902,000	$ 43,798,000	$ 55,030,000
10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Interest rate percentage									10.25%
Redemption price, percentage					101.00%
Convertible debt | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Maximum borrowing capacity									$ 150,000,000
Current borrowing capacity									80,000,000
Convertible debt | Convertible Promissory Notes Interest Rate 6% Due December 2020, Recourse | Affiliated entity
Debt Instrument [Line Items]
Interest rate percentage			6.00%		6.00%
Notes | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Debt face amount									70,000,000
Interest rate percentage			10.25%		10.25%			10.25%
Secured long-term debt, noncurrent									$ 64,000,000
Long-term debt, current maturities			$ 6,034,000		$ 6,034,000			$ 0
Long-term debt, gross			$ 70,000,000		$ 70,000,000			$ 70,000,000
Senior secured notes | 2.5% Green Convertible Senior Notes due August 2025
Debt Instrument [Line Items]
Interest rate percentage		2.50%	2.50%		2.50%			2.50%
Long-term debt, current maturities			$ 0		$ 0			$ 0
Long-term debt, gross		$ 230,000,000	230,000,000		$ 230,000,000			$ 230,000,000
Debt instrument, unamortized discount		6,900,000
Debt other issuance costs, net		3,000,000
Proceeds from debt, net of issuance costs		$ 220,100,000
Convertible, conversion ratio					0.0616808
Contractual interest expense			1,900,000		$ 5,800,000
Amortization of debt issuance costs			$ 500,000		$ 1,500,000
Senior secured notes | 2.5% Green Convertible Senior Notes due August 2025 | Accounting Standards Update 2020-06
Debt Instrument [Line Items]
Accumulated deficit							$ 5,300,000
Decrease in additional paid-in capital							126,800,000
Non-recourse long term debt, non-current							$ 121,500,000
Class A common stock | Senior secured notes | 2.5% Green Convertible Senior Notes due August 2025
Debt Instrument [Line Items]
Convertible stock price (in dollars per share) | $ / shares		$ 16.21
On or after March 27, 2022 | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Redemption price, percentage					108.00%
On or after March 27, 2023 | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Redemption price, percentage					104.00%
On or after March 27, 2024 | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Redemption price, percentage					102.00%
On or after March 27, 2026 | 10.25% Senior Secured Notes due March 2027
Debt Instrument [Line Items]
Redemption price, percentage					100.00%

[1] We have variable interest entities, which represent a portion of the consolidated balances recorded within these financial statement line items in the condensed consolidated balance sheets (see Note 11 - Portfolio Financings).