Joint Venture Transaction (Pro Forma) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Business Combinations [Abstract]
Net income (loss)	$ 73,640	$ 3,378	$ 84,408	$ (45,201)
Income (loss) per share/unit - basic (usd per share)	$ 0.50	$ (0.06)	$ 0.43	$ (0.57)
Income (loss) per share/unit - diluted (usd per share)	$ 0.50	$ (0.06)	$ 0.42	$ (0.57)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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No definition available.

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