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Basis of Presentation and Summary of Significant Accounting Policies (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Disaggregation of Revenue [Line Items] |  |
Revenue from contract with customer, excluding assessed tax | $ 4,604 | $ 3,247
Add: non-ASC 606 rental revenue | 13,387 | 11,471
Revenue | 17,991 | 14,718
Compressors - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contract with customer, excluding assessed tax | 2,708 | 1,829
Flares - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contract with customer, excluding assessed tax | 435 | 522
Other (Parts/Rebuilds) - sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contract with customer, excluding assessed tax | 982 | 647
Service and maintenance |  |
Disaggregation of Revenue [Line Items] |  |
Revenue from contract with customer, excluding assessed tax | 479 | 249
Revenue | $ 479 | $ 249

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- Definition Income earned by providing the use of assets to an outside party in exchange for a payment or series of payments that is nonoperating in nature. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
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