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Summary of Significant Accounting Policies (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 2,274	$ 6,323	$ 4,064	$ 10,927
Add: ASC 842 rental revenue	15,131	13,572	31,231	26,959
Total revenue	17,405	19,895	35,295	37,886
Compressors - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,360	4,788	2,212	7,496
Flares - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	160	106	240	541
Other (parts/rebuilds) - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	488	920	1,006	1,902
Service and maintenance
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 266	$ 509	$ 606	$ 988

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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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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