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Summary of Significant Accounting Policies - Narrative (Details) | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) segment | Dec. 31, 2019 USD ($)
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 | $ 1,161,000 | $ 918,000
Revenues | 68,055,000 | 78,444,000
Revenue recognized | $ 73,000 | 48,000
Amortization period of capitalized contract costs | 1 year |
Impairment of goodwill | $ 0 | 10,039,000
Product warranty reserves | 0 | 74,000
Uncertain tax positions | $ 0 |
Number of business segments | segment | 1 |
Minimum |  |
Revenue from External Customer [Line Items] |  |
Rental contract term | 6 months |
Property and equipment, estimated useful life | 3 years |
Minimum | Rental Equipment |  |
Revenue from External Customer [Line Items] |  |
Property and equipment, estimated useful life | 15 years |
Maximum |  |
Revenue from External Customer [Line Items] |  |
Rental contract term | 60 months |
Property and equipment, estimated useful life | 39 years |
Maximum | Rental Equipment |  |
Revenue from External Customer [Line Items] |  |
Property and equipment, estimated useful life | 25 years |
Developed Technology |  |
Revenue from External Customer [Line Items] |  |
Intangible assets, useful life | 20 years |
Intangible assets, weighted average remaining life | 5 years |
Bill and Hold Arrangement |  |
Revenue from External Customer [Line Items] |  |
Revenues | $ 900,000 | $ 11,600,000
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 | One Customer | Accounts Receivable |  |
Revenue from External Customer [Line Items] |  |
Concentration risk, percentage | 35.00% | 35.00%
Customer Concentration Risk | Oxy | Sales and Rental Income |  |
Revenue from External Customer [Line Items] |  |
Concentration risk, percentage | 30.00% | 36.00%

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