Inventories (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Inventory valuation adjustment	$ 1,187us-gaap_InventoryWriteDown	$ 0us-gaap_InventoryWriteDown
Components of Inventories
Crude oil	55,680us-gaap_EnergyRelatedInventoryPetroleum		26,722us-gaap_EnergyRelatedInventoryPetroleum
Asphalt and other	12,090		16,810
Total Inventories	67,770us-gaap_InventoryNet		43,532us-gaap_InventoryNet
Crude [Member] \| Crude Oil [Member]
Inventory valuation adjustment	$ 1,200

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Carrying amount as of the balance sheet date of other types of fuel derived from living matter of a previous geologic time, not otherwise itemized.

+ References

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

+ References

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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

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-Section S99

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-Subparagraph (SX 210.5-02.6(a))

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Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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