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Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Revenue from External Customer [Line Items]
Revenues	$ 17,749	$ 17,405	$ 36,146	$ 35,295
Revenue related to unsatisfied performance obligations	0		0
Uncertain tax position	$ 0		$ 0
Minimum
Revenue from External Customer [Line Items]
Amortization period of capitalized contract costs	1 year		1 year
Minimum | Rental Contracts, Excluding Large Horsepower Compressors
Revenue from External Customer [Line Items]
Rental contract term	6 months		6 months
Maximum | Rental Contracts, Excluding Large Horsepower Compressors
Revenue from External Customer [Line Items]
Rental contract term	24 months		24 months
Maximum | Rental Contracts, Large Horsepower Compressors
Revenue from External Customer [Line Items]
Rental contract term	60 months		60 months
Sales
Revenue from External Customer [Line Items]
Revenues	$ 1,573	$ 2,008	$ 4,284	3,458
Revenue recognized			1,100		$ 533
Rental income
Revenue from External Customer [Line Items]
Revenue recognized			$ 2		$ 73
Bill and Hold Arrangement
Revenue from External Customer [Line Items]
Revenues	$ 0			$ 852

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