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Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Disaggregation of Revenue [Line Items] |  |
Revenue from contracts with customers | $ 7,229 | $ 21,743
Add: ASC 842 rental revenue | 60,826 | 56,701
Total revenue | 68,055 | 78,444
Compressors - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contracts with customers | 2,211 | 15,185
Flares - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contracts with customers | 489 | 959
Other (Parts/Rebuilds) - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contracts with customers | 2,957 | 3,619
Service and maintenance |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contracts with customers | $ 1,572 | $ 1,980

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