Related Party Transactions - Debt to Related Parties (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Unpaid Principal Balance	$ 707,239	$ 658,083
Current portion of debt	129,657	337,583
Long-term portion of debt	440,690	299,229
Total	570,347	636,812
Affiliated entity
Related Party Transaction [Line Items]
Unpaid Principal Balance		59,138
Current portion of debt		24,683
Long-term portion of debt		31,088
Total		55,771
Term Loan due September 2028, Non-Recourse \| Term loan
Related Party Transaction [Line Items]
Unpaid Principal Balance	35,087	38,337
Current portion of debt	2,696	3,882
Long-term portion of debt	29,522	31,087
Total	$ 32,218	34,969
Term Loan due September 2028, Non-Recourse \| Term loan \| Affiliated entity
Related Party Transaction [Line Items]
Unpaid Principal Balance		38,337
Current portion of debt		3,882
Long-term portion of debt		31,088
Total		34,970
Convertible Promissory Notes Interest Rate 6% Due December 2020, Recourse \| Convertible promissory notes
Related Party Transaction [Line Items]
Unpaid Principal Balance		289,299
Current portion of debt		273,410
Long-term portion of debt		0
Total		273,410
Convertible Promissory Notes Interest Rate 6% Due December 2020, Recourse \| Term loan \| Affiliated entity \| PPA IIIa
Related Party Transaction [Line Items]
Unpaid Principal Balance		20,801
Current portion of debt		20,801
Long-term portion of debt		0
Total		$ 20,801

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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