For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Amount of interest expense incurred on a debt or other obligation to related party.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Revenue from related parties	$ 75,703	$ 172	$ 168,908	$ 31,097
Revenue	233,471	190,190	667,960	528,432
Interest paid			35,894	30,601
Interest expense on debt to related parties	1,605	1,966	4,823	7,265
Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Accounts receivable	300		300		$ 3,300
Revenue from related parties	200			31,100
Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Accounts receivable	1,000		1,000
Revenue from related parties	74,700		166,400
PPA II
Related Party Transaction [Line Items]
Repayments of debt			144,813		65,114
PPA IIIa
Related Party Transaction [Line Items]
Repayments of debt			6,122		$ 4,431
PPA IIIa \| Term loan \| Term Loan due September 2028, Non-Recourse \| Affiliated entity
Related Party Transaction [Line Items]
Repayments of debt	500	800	1,700	2,300
Service
Related Party Transaction [Line Items]
Revenue	23,597	20,751	70,546	60,633
Service \| Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	1,000		2,528
Product
Related Party Transaction [Line Items]
Revenue	182,616	125,690	504,249	355,651
Product \| Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	71,500		159,300
Installation
Related Party Transaction [Line Items]
Revenue	19,010	$ 29,690	58,553	$ 70,053
Installation \| Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	$ 3,200		7,100
Consulting Agreement \| General Colin L. Powell \| Director
Related Party Transaction [Line Items]
Related party amount of transaction			$ 125