Inventories (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Inventory valuation adjustment	$ 0	$ 1,235
Components of Inventories
Crude oil	76,343		$ 59,121
Asphalt and other	9,117		11,118
Total Inventories	$ 85,460		$ 70,239
Crude Supply and Logistics [Member] \| Crude Oil [Member]
Inventory valuation adjustment		$ 1,200

No definition available.

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- Definition

Amount of fossil fuel included in inventory classified as other.

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Carrying amount as of the balance sheet date of petroleum or crude oil.

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 35
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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66092785&loc=d3e4542-108314

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