Supplemental Information On Oil And Gas Exploration And Production Activities (Results of Operations for Producing Activities) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Results of Operations for Oil and Gas Producing Activities [Line Items]
Revenues	$ 670,762,000	$ 262,225,000	$ 248,601,000
Production costs	(140,664,000)	(64,666,000)	(53,708,000)
Depletion	(263,946,000)	(118,118,000)	(90,230,000)
Results of operations, before income taxes	266,152,000	79,441,000	104,663,000
Current	0	0	730,000
Deferred	96,061,000	49,447,000	25,633,000
Income tax expense	96,061,000	49,447,000	26,363,000
Results of operations from producing activities	170,091,000	29,994,000	78,300,000
Depletion per MCF of Gas Equivalent	3.01gpor_DepletionperMCFofGasEquivalent	4.78gpor_DepletionperMCFofGasEquivalent	5.85gpor_DepletionperMCFofGasEquivalent
Diamondback Energy, Inc [Member]
Results of Operations for Oil and Gas Producing Activities [Line Items]
Revenues	0	14,976,000	16,042,000
Production costs	0	(2,518,000)	(4,474,000)
Depletion	0	(4,754,000)	(5,515,000)
Results of operations, before income taxes	0	7,704,000	6,053,000
Income tax expense	0	2,286,000	2,158,000
Results of operations from producing activities	0	5,418,000	3,895,000
Grizzly Oil Sands ULC [Member]
Results of Operations for Oil and Gas Producing Activities [Line Items]
Revenues	5,449,000	0	0
Production costs	(10,113,000)	0	0
Depletion	(1,195,000)	0	0
Results of operations, before income taxes	(5,859,000)	0	0
Income tax expense	0	0	0
Results of operations from producing activities	$ (5,859,000)	$ 0	$ 0

Depletion per MCF of Gas Equivalent

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Results of operations income tax expense current

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Results of operations income tax expense deferred

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Depreciation, depletion and amortization, and valuation provisions (impairments) related to oil and gas producing activities.

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Income before income taxes for oil and gas producing activities.

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Income tax expense for oil and gas producing activities.

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

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The results of operations for oil and gas producing activities, excluding corporate overhead and interest costs.

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Production (lifting) costs from oil and gas producing activities, including but not limited to lease operating expense, production and ad valorem taxes, and transportation expense.

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Total revenues from oil and gas producing activities.

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