Number of persons employed by the Entity

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- Definition

Level 2 and level 3 fair value transactions

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Number of Customers

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of employees expire in year one collective bargaining agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
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- Definition

Number of Employees, Renewing Collective Bargaining Agreements

+ References

No definition available.

+ Details

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- Definition

Number of Suppliers

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

purchases of product

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

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Reference 2: 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=6927468&loc=d3e6404-108592

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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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 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226016-175313

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=34720828&loc=SL20225862-175312

Reference 3: 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=35706170&loc=d3e41678-113959

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 22

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226052-175313

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: 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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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

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

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Financial Instruments and Concentrations of Risk (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014 employees	Dec. 31, 2013	Dec. 31, 2012
Level 2 and level 3 fair value transactions	$ 0	$ 0	$ 0
Margin deposits	800,000us-gaap_MarginDepositAssets	800,000us-gaap_MarginDepositAssets
Derivative Asset, Fair Value, Amount Offset Against Collateral	2,500,000	800,000
Fair Value Adjustment of Warrants	13,423,000us-gaap_FairValueAdjustmentOfWarrants	46,433,000us-gaap_FairValueAdjustmentOfWarrants	21,310,000us-gaap_FairValueAdjustmentOfWarrants
Number of employees	1,080dei_EntityNumberOfEmployees
Unionized Employees Concentration Risk [Member] \| Canada And Mexico [Member]
Number of employees	130
Number of employees with contracts expiring in collective bargaining agreements	70
Number of employees with contracts renewing collective bargaining agreements	60
Sales Revenue, Goods, Net [Member] \| Crude [Member]
Number of customers	1
Sales Revenue, Goods, Net [Member] \| Customer Concentration Risk [Member] \| Crude [Member]
Percentage of accounts receivables	36.00%
Cost of Goods, Total [Member] \| Crude [Member]
purchases of product	469,000,000
Cost of Goods, Total [Member] \| Customer Concentration Risk [Member] \| Crude [Member]
Number of Suppliers	1
Percentage of accounts receivables	29.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Crude [Member]
Number of customers	2
Percentage of accounts receivables	34.00%
Warrant [Member] \| Fair Value, Inputs, Level 1 [Member]
Warrant liability		$ 58,100,000
Outside Of United States [Member]
Number of employees	540