Revenue Recognition - Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 141,324	$ 130,030
Total revenue	156,699	147,001
Product
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	99,559	90,926
Total revenue	99,559	90,926
Installation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16,618	12,219
Total revenue	16,618	12,219
Service
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	25,147	23,467
Total revenue	25,147	23,467
Electricity
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	3,418
Operating lease revenue	15,375	16,971
Total revenue	$ 15,375	$ 20,389

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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