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Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)
Revenue from External Customer [Line Items]
Cash equivalents, qualification, maximum original maturity of short-term investments	3 months
Customer deposit requirements, large custom contracts, maximum percentage	50.00%
Allowance for doubtful accounts	$ 1,129	$ 1,161
Revenues	72,420	68,055
Revenue recognized	$ 1,100	73
Amortization period of capitalized contract costs	1 year
Product warranty reserves	$ 0	$ 0
Uncertain tax positions	$ 0
Number of business segments | segment	1
Developed Technology
Revenue from External Customer [Line Items]
Intangible assets, useful life	20 years	20 years
Intangible assets, weighted average remaining life	4 years
Bill and Hold Arrangement
Revenue from External Customer [Line Items]
Revenues	$ 20	$ 852
Minimum
Revenue from External Customer [Line Items]
Rental contract term	6 months
Property and equipment, estimated useful life	3 years
Maximum
Revenue from External Customer [Line Items]
Rental contract term	60 months
Property and equipment, estimated useful life	39 years
Rental Contracts, Excluding Large Horsepower Compressors | Minimum
Revenue from External Customer [Line Items]
Rental contract term	6 months
Rental Contracts, Excluding Large Horsepower Compressors | Maximum
Revenue from External Customer [Line Items]
Rental contract term	24 months
Rental Contracts, Large Horsepower Compressors | Maximum
Revenue from External Customer [Line Items]
Rental contract term	60 months
Customer Concentration Risk | Oxy | Sales and Rental Income
Revenue from External Customer [Line Items]
Concentration risk, percentage	40.00%	30.00%
Customer Concentration Risk | Oxy | Accounts Receivable
Revenue from External Customer [Line Items]
Concentration risk, percentage	46.00%	35.00%

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