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Basis of Presentation and Summary of Significant Accounting Policies Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	$ 7,835	$ 11,752
Rental revenue	6,883	7,150
Revenue	14,718	18,902
Compressors
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	1,829	5,640
Flares
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	522	269
Service & Maintenance
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	4,837	5,116
Revenue	249	343
Other (Parts/Rebuilds)
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	$ 4,837	$ 5,116

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 32
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-URI http://asc.fasb.org/extlink&oid=82859839&loc=SL82860478-203043

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 225
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