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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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