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Inventory Allowance and Retirement of Long-Lived Assets (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2019 USD ($) compressor | Sep. 30, 2018 USD ($) | Dec. 31, 2018 USD ($)
Impaired Assets to be Disposed of by Method Other than Sale [Line Items] |  |  |  |
Inventory allowance | $ 3,350 | $ 3,350 | $ 0 |
Allowance for obsolescence | 3,371 | 3,371 |  | $ 19
Loss on retirement of rental equipment | $ 1,512 | $ 1,512 | $ 0 |
Rental Compressor Unit |  |  |  |
Impaired Assets to be Disposed of by Method Other than Sale [Line Items] |  |  |  |
Number of units retired | compressor |  | 327 |  |
Rental Compressor Unit | Loss On Retirement of Rental Equipment |  |  |  |
Impaired Assets to be Disposed of by Method Other than Sale [Line Items] |  |  |  |
Loss on retirement of rental equipment |  | $ 1,500 |  |

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- Definition Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 + Details
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