Number of persons employed by the Entity

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

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- Definition

Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41678-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313

+ Details

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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

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.

+ 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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Financial Instruments and Concentrations of Risk (Details Textual) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($) employees	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) employees	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Margin deposits	$ 3,600				$ 2,900				$ 3,600	$ 2,900
Derivative Asset, Fair Value, Amount Offset Against Collateral	2,300				2,600				2,300	2,600
Fair Value Adjustment of Warrants									0	0	$ 13,423
Revenue, Net	$ 402,172	$ 327,764	$ 287,377	$ 314,851	$ 382,493	$ 397,065	$ 377,226	$ 298,310	1,332,164	1,455,094	2,122,579
SemGas [Member]
Revenue, Net									$ 208,042	$ 231,569	$ 342,286
Number of Employees, Geographic Area [Member] \| Geographic Concentration Risk [Member]
Number of employees \| employees	1,140								1,140
Non-US [Member] \| Number of Employees, Geographic Area [Member] \| Geographic Concentration Risk [Member]
Number of employees	550								550
Mexico and Canada [Member] \| Workforce Subject to Collective Bargaining Arrangements [Member] \| Unionized Employees Concentration Risk [Member]
Number of employees	130								130
Largest Customer [Member] \| Sales Revenue, Net [Member] \| Customer Concentration Risk [Member]
Revenue, Net									$ 313,800
Largest Customer [Member] \| Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Concentration of risk, percentage									20.00%
Three Largest Producers [Member] \| Processing volumes [Member] \| Product Concentration Risk [Member] \| SemGas [Member]
Concentration of risk, percentage									92.00%
Three Largest Producers [Member] \| Gathering volumes [Member] \| Product Concentration Risk [Member] \| SemGas [Member]
Concentration of risk, percentage									95.00%
Agreements With Annual Renewals [Member] \| Mexico and Canada [Member] \| Workforce Subject to Collective Bargaining Arrangements [Member] \| Unionized Employees Concentration Risk [Member]
Number of employees	70								70
Expired Agreements Being Renegotiated [Member] \| Mexico and Canada [Member] \| Workforce Subject to Collective Bargaining Arrangements [Member] \| Unionized Employees Concentration Risk [Member]
Number of employees	60								60