Number of persons employed by the Entity

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- Definition

Level 2 and level 3 fair value transactions

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No definition available.

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- Definition

Number of Customers

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No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Number of employees expire in year one collective bargaining agreements.

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No definition available.

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- Definition

Number of Employees, Renewing Collective Bargaining Agreements

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No definition available.

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- Definition

Number of Suppliers

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No definition available.

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- Definition

Number of producers

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No definition available.

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- Definition

purchases of product

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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

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-Name Accounting Standards Codification
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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

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-Name Accounting Standards Codification
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-Paragraph 8
-Subparagraph (a)
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- Definition

Fair value of financial liability or 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, not subject to a master netting arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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Balance Type:	debit
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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

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-Publisher FASB
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-Paragraph 1
-Subparagraph (SX 210.5-02.8,17)
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- Definition

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

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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Financial Instruments and Concentrations of Risk (Details Textual)	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($) employees	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) employees Customer	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Level 2 and level 3 fair value transactions									$ 0	$ 0	$ 0
Margin deposits	$ 2,900,000				$ 800,000				2,900,000	800,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	2,600,000				2,500,000				2,600,000	2,500,000
Fair Value Adjustment of Warrants									0	13,423,000	46,433,000
Revenues	$ 382,493,000	$ 397,065,000	$ 377,226,000	$ 298,310,000	$ 547,237,000	$ 594,235,000	$ 482,224,000	$ 498,883,000	$ 1,455,094,000	$ 2,122,579,000	1,427,016,000
Number of employees \| employees	1,160								1,160
Unionized Employees Concentration Risk [Member] \| Canada And Mexico [Member]
Number of employees	130								130
Number of employees with contracts expiring in collective bargaining agreements	68								68
Number of employees with contracts renewing collective bargaining agreements \| employees	60								60
Sales Revenue, Goods, Net [Member] \| Crude Supply and Logistics [Member]
Number of customers \| Customer									2
Cost of Goods, Total [Member] \| Crude Supply and Logistics [Member]
purchases of product									$ 232,600,000
Cost of Goods, Total [Member] \| Customer Concentration Risk [Member] \| Crude Supply and Logistics [Member]
Number of Suppliers									2
Concentration of risk, percentage									24.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Crude Supply and Logistics [Member]
Number of customers \| Customer									1
Concentration of risk, percentage									39.00%
Processing volumes [Member] \| SemGas [Member]
Concentration of risk, percentage									92.00%
Number of producers \| Customer									3
Gathering volumes [Member] \| SemGas [Member]
Concentration of risk, percentage									93.00%
Number of producers \| Customer									3
Warrant [Member] \| Fair Value, Inputs, Level 1 [Member]
Warrant liability											$ 58,100,000
Outside Of United States [Member]
Number of employees	555								555
Shell Trading Company [Member] \| Sales Revenue, Net [Member] \| Customer Concentration Risk [Member]
Revenues									$ 457,300,000
BP Oil Supply Company [Member] \| Sales Revenue, Net [Member] \| Customer Concentration Risk [Member]
Revenues									$ 146,200,000