Other Financial Information (Schedule of Renewable Identification Numbers (RINs) and Other Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Financial Information [Abstract]
Renewable Identification Numbers (RINs) sales	$ 48,047	$ 20,037	$ 130,690	$ 93,883
Other	772	717	2,940	2,331
Other operating revenues	$ 48,819	$ 20,754	$ 133,630	$ 96,214

Amount, after sales adjustments, returns, allowances, and discounts, of revenue classified as other.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a),(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration