Related Party Transactions - Debt to Related Parties (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Unpaid Principal Balance	$ 640,626	$ 658,083
Current portion of debt	26,064	337,583
Long-term portion of debt	619,655	299,229
Total	645,719	636,812
Affiliated entity
Related Party Transaction [Line Items]
Unpaid Principal Balance	50,801	59,138
Current portion of debt	0	24,683
Long-term portion of debt	53,675	31,088
Total	53,675	55,771
Convertible Promissory Notes Interest Rate 10% Due December 2021 \| Term loan \| Affiliated entity \| PPA IIIa
Related Party Transaction [Line Items]
Unpaid Principal Balance	50,801
Current portion of debt	0
Long-term portion of debt	53,675
Total	53,675
Term Loan due September 2028, Non-Recourse \| Term loan
Related Party Transaction [Line Items]
Unpaid Principal Balance	35,675	38,337
Current portion of debt	2,567	3,882
Long-term portion of debt	30,078	31,087
Total	$ 32,645	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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