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Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)
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	$ 338,000	$ 1,129,000
Revenues	84,825,000	72,420,000
Revenue recognized	$ 1,300,000	1,100,000
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	$ 0	$ 20,000
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	42.00%	40.00%
Customer Concentration Risk | Oxy | Accounts Receivable
Revenue from External Customer [Line Items]
Concentration risk, percentage	55.00%	46.00%

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