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Rental Equipment, Property and Equipment (Narrative) (Details) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Sep. 30, 2018 USD ($) | Jun. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) compressor $ / shares | Dec. 31, 2018 USD ($) compressor | Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation |  |  |  |  |  |  |  |  | $ 23,143 | $ 21,954 | $ 21,191
Net income (loss) | $ (1,710) | $ (12,579) | $ 327 | $ 98 | $ (749) | $ (118) | $ 211 | $ 190 | (13,864) | (466) | 19,794
Retirement of rental equipment |  |  |  |  |  |  |  |  | 1,512 | 0 | 0
Property, Plant, and Equipment, Excluding Rental Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation |  |  |  |  |  |  |  |  | $ 1,700 | $ 1,100 | 1,200
Rental Compressor Unit |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of units retired | compressor |  |  |  |  |  |  |  |  | 327 | 13 |
Rental Compressor Unit | Loss On Retirement of Rental Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Retirement of rental equipment |  |  |  |  |  |  |  |  | $ 1,500 |  |
Revisions | Revision Of Prior Period Financial Statements |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation |  |  |  |  |  |  |  |  | 1,470 |  |
Net income (loss) |  | $ (347) | $ (246) | $ (259) | $ (467) | $ (354) | $ (36) | $ (35) | $ 1,130 | $ (892) | (57)
Earnings per share, basic and diluted (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 0.09 |  |
Rental Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation |  |  |  |  |  |  |  |  | $ 21,400 | $ 20,900 | $ 20,000
Rental Equipment | Compressor Units, 1,380 Horsepower |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 25 years |  |
Minimum |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 3 years |  |
Minimum | Rental Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 15 years |  |
Minimum | Rental Equipment | Compressor Units, 400-600 Horsepower |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 15 years |  |
Minimum | Rental Equipment | Compressor Unit, Peer Horsepower |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 20 years |  |
Maximum |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 39 years |  |
Maximum | Rental Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 25 years |  |
Maximum | Rental Equipment | Compressor Units, 400-600 Horsepower |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 20 years |  |
Maximum | Rental Equipment | Compressor Unit, Peer Horsepower |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Useful Lives |  |  |  |  |  |  |  |  | 30 years |  |

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