Financial Instruments (Details Textual) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) Customer	Dec. 31, 2015 USD ($)
Offsetting Assets [Line Items]
Margin Deposit Assets \| $	$ (1.0)	$ 2.9
Commodity Contract [Member]
Offsetting Assets [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral \| $	$ 3.2	$ 2.6
Customer Concentration Risk [Member] \| Sales Revenue, Goods, Net [Member]
Offsetting Assets [Line Items]
Concentration Risk, Percentage	35.00%
Customer Concentration Risk [Member] \| Cost of Goods, Total [Member]
Offsetting Assets [Line Items]
Concentration Risk, Percentage	14.00%
Number of Suppliers \| Customer	1
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Offsetting Assets [Line Items]
Concentration Risk, Percentage	34.00%
Customer Concentration Risk [Member] \| Crude Supply and Logistics [Member] \| Sales Revenue, Goods, Net [Member]
Offsetting Assets [Line Items]
Number of Customers \| Customer	1
Customer Concentration Risk [Member] \| Crude Supply and Logistics [Member] \| Cost of Goods, Total [Member]
Offsetting Assets [Line Items]
Purchases of product \| $	$ 27.9
Customer Concentration Risk [Member] \| Crude Supply and Logistics [Member] \| Accounts Receivable [Member]
Offsetting Assets [Line Items]
Number of Customers \| Customer	1

Number of Customers

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- Definition

Number of Suppliers

+ References

No definition available.

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- Definition

purchases of product

+ References

No definition available.

+ Details

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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=51801978&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=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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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=56946850&loc=d3e41678-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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