Oil and Natural Gas Properties (Unaudited Pro Forma Financial Information) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Oil and Natural Gas Properties [Abstract]
Revenues	$ 48,035	$ 43,253	$ 142,040	$ 114,078
Income from operations	15,269	13,721	45,453	28,481
Income available to common stockholders	$ 11,102	$ 766	$ 16,571	$ 2,477
Basic	$ 0.19	$ 0.01	$ 0.30	$ 0.05
Diluted	$ 0.19	$ 0.01	$ 0.29	$ 0.05

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 income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the 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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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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