Discontinued Operations (Cash Flow Information) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Net cash provided by (used in) discontinued operating activities	$ (17,887)	$ 28,876	$ 80,558
Hereford Production Facility [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Net cash provided by (used in) discontinued operating activities	(17,887)	28,741	30,810
Net cash provided by (used in) discontinued investing activities	$ 86,322	$ (4,918)	$ (1,959)

Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=51717284&loc=SL51721673-107760

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration