The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 958
-SubTopic 225
-Section 45
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84241808&loc=d3e92212-112881

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Represents the number of compressor units that are to be retired or sold or reutilized.

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Represents the number of horsepower units that are to be retired or sold or reutilized

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Organization and Summary of Significant Accounting Policies - Property and Equipment (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($) item
Property and Equipment
Number of compressor units that are to be retired or sold or reutilized.		2
Number of horsepower that are to be retired or sold or reutilized.		2,760
Impairments of long-lived assets
Impairment of long-lived assets \| $	$ 0.0	$ 1.1
Newly acquired compression equipment
Property and Equipment
Estimated useful lives	25 years
Used compression equipment \| Minimum
Property and Equipment
Estimated useful lives	9 years
Used compression equipment \| Maximum
Property and Equipment
Estimated useful lives	25 years
Compression equipment overhauls \| Minimum
Property and Equipment
Estimated useful lives	3 years
Compression equipment overhauls \| Maximum
Property and Equipment
Estimated useful lives	5 years
Furniture and fixtures
Property and Equipment
Estimated useful lives	7 years
Vehicles and computer equipment \| Minimum
Property and Equipment
Estimated useful lives	3 years
Vehicles and computer equipment \| Maximum
Property and Equipment
Estimated useful lives	7 years
Leasehold improvements
Property and Equipment
Estimated useful lives	5 years