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Summary of Significant Accounting Policies (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 904	$ 6,418	$ 4,968	$ 17,345
Add: ASC 842 rental revenue	14,861	14,434	46,092	41,393
Total revenue	15,765	20,852	51,060	58,738
Compressors - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	4,703	2,211	12,199
Flares - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	67	243	308	783
Other (parts/rebuilds) - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	469	931	1,475	2,834
Service and maintenance
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 368	$ 541	$ 974	$ 1,529

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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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