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 ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Revenue from related parties			$ 93,204,000	$ 30,925,000
Revenue	$ 233,782,000	$ 168,881,000	434,489,000	338,242,000
Interest paid			23,867,000	16,540,000
Interest expense on debt to related parties	1,606,000	2,672,000	3,218,000	5,299,000
Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Accounts receivable	9,800		9,800		$ 3,300,000
Revenue from related parties	1,700,000			30,900,000
Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties			91,600,000
Consulting Agreement \| General Colin L. Powell \| Director
Related Party Transaction [Line Items]
Related party amount of transaction			125,000
PPA II
Related Party Transaction [Line Items]
Repayments of debt			144,813,000		65,114,000
PPA IIIa
Related Party Transaction [Line Items]
Repayments of debt			5,651,000		$ 4,431,000
PPA IIIa \| Term loan \| Term Loan due September 2028, Non-Recourse \| Affiliated entity
Related Party Transaction [Line Items]
Repayments of debt	400,000		1,200,000
Interest paid	700,000		1,500,000
Service
Related Party Transaction [Line Items]
Revenue	23,659,000	19,975,000	46,949,000	39,882,000
Service \| Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	800,000	200,000	1,568,000	300,000
Product
Related Party Transaction [Line Items]
Revenue	179,899,000	108,654,000	321,633,000	229,961,000
Product \| Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties				28,300,000
Product \| Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	87,700,000
Installation
Related Party Transaction [Line Items]
Revenue	17,285,000	26,245,000	$ 39,543,000	40,363,000
Installation \| Softbank Corp. \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties		$ 1,500,000		$ 2,300,000
Installation \| Diamond State Generation Partners, LLC \| Equity method investee
Related Party Transaction [Line Items]
Revenue from related parties	$ 3,900,000