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Summary of Significant Accounting Policies (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 21,743	$ 17,712	$ 21,647
Add: ASC 842 rental revenue									56,701	47,766	46,046
Total revenue	$ 19,706	$ 20,852	$ 19,895	$ 17,991	$ 16,160	$ 16,396	$ 18,204	$ 14,718	78,444	65,478	67,693
Compressors - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									15,185	10,994	13,382
Flares - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									959	2,535	2,755
Other (Parts/Rebuilds) - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									3,619	2,740	4,071
Service and maintenance
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 1,980	$ 1,443	$ 1,439

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Income earned by providing the use of assets to an outside party in exchange for a payment or series of payments that is nonoperating in nature.

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-Publisher FASB
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