Segment Reporting - Schedule of Financial Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total revenue	$ 47,256			$ 8,650			$ 112,083	$ 11,324
Operating expenses excluding depreciation and amortization	(53,081)			(10,498)			(127,139)	(14,974)
Depreciation and amortization	(2,036)			(100)			(4,794)	(510)
Net loss	(4,216)	$ (7,010)	$ (7,435)	(2,913)	$ (2,648)	$ 102	(18,661)	(5,459)	$ (1,400)
Trucking [Member]
Segment Reporting Information [Line Items]
Total revenue	47,159			8,235			111,375	10,212
CNG Fueling Stations [Member]
Segment Reporting Information [Line Items]
Total revenue	97			415			708	1,112
Operating Segment [Member] | Trucking [Member]
Segment Reporting Information [Line Items]
Total revenue	47,159			8,235			111,375	10,212
Operating expenses excluding depreciation and amortization	(50,449)			(9,007)			(120,799)	(11,111)
Depreciation and amortization	(1,785)			(14)			(4,260)	(97)
Net loss	(6,293)			(907)			(16,183)	(1,151)
Operating Segment [Member] | CNG Fueling Stations [Member]
Segment Reporting Information [Line Items]
Total revenue	97			415			708	1,112
Operating expenses excluding depreciation and amortization	205			(1,560)			(746)	(2,147)
Depreciation and amortization	(113)			(86)			(377)	(413)
Net loss	181			(1,628)			(453)	(1,846)
Corporate and Unallocated [Member]
Segment Reporting Information [Line Items]
Operating expenses excluding depreciation and amortization	(2,837)			69			(5,594)	(1,716)
Depreciation and amortization	(138)						(157)
Net loss	$ 1,896			$ (378)			$ (2,025)	$ (2,462)