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Basis of Presentation and Summary of Significant Accounting Policies (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	$ 6,323	$ 6,777	$ 10,927	$ 10,024
Add: non-ASC 606 rental revenue	13,572	11,427	26,959	22,898
Revenue	19,895	18,204	37,886	32,922
Compressors - sales
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	4,788	4,735	7,496	6,564
Flares - sales
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	106	969	541	1,491
Other (Parts/Rebuilds) - sales
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	920	679	1,902	1,326
Service and maintenance
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax	509	394	988	643
Revenue	$ 509	$ 394	$ 988	$ 643

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+ References

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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-Topic 220
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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