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Rental Equipment, Property and Equipment - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) compressor	Dec. 31, 2019 USD ($) compressor
Property, Plant and Equipment [Line Items]
Depreciation	$ 25,073	$ 23,143
Retirement of rental equipment	291	1,512
Loss On Retirement of Rental Equipment
Property, Plant and Equipment [Line Items]
Retirement of rental equipment	291	1,512
Property, Plant, and Equipment, Excluding Rental Equipment
Property, Plant and Equipment [Line Items]
Depreciation	$ 2,300	$ 1,700
Rental Compressor Unit
Property, Plant and Equipment [Line Items]
Number of units retired | compressor	216	327
Rental Equipment
Property, Plant and Equipment [Line Items]
Depreciation	$ 22,700	$ 21,400
Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	3 years
Minimum | Rental Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	15 years
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	39 years
Maximum | Rental Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	25 years

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value.

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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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