Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Revenue from Contracts with Customers
Revenue	$ 86,006	$ 77,698
Receivables, net	58,685		$ 61,760
Contract Assets - Current	927		455
Contract Assets - Noncurrent	3,840		3,777
Contract Assets - Total	4,767		4,232
Contract Liabilities - Current	5,781		5,329
Contract Liabilities - Noncurrent	3,401		6,339
Contract Liabilities - Total	9,182		$ 11,668
Volume -Related
Revenue from Contracts with Customers
Revenue	75,060	74,528
Volume -Related \| Commodity swaps
Revenue from Contracts with Customers
Revenue	9,400	5,000
Volume -Related \| Fueling agreements
Revenue from Contracts with Customers
Revenue	3,800
Station construction sales
Revenue from Contracts with Customers
Revenue	5,522	$ 3,170
AFTC
Revenue from Contracts with Customers
Revenue	$ 5,424

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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