Capital Expenditures, Cash and Non-Cash

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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-Publisher FASB

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-Topic 932

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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-Publisher FASB

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-Topic 235

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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- Definition

Aggregate revenue during the period related to oil and gas business activities.

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-Topic 225

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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Business Segment Information - Summarized Financial Information of Segments (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Total revenues	$ 299,672,000us-gaap_OilAndGasRevenue	$ 368,659,000us-gaap_OilAndGasRevenue	$ 372,378,000us-gaap_OilAndGasRevenue	$ 349,519,000us-gaap_OilAndGasRevenue	$ 333,615,000us-gaap_OilAndGasRevenue	$ 305,498,000us-gaap_OilAndGasRevenue	$ 254,582,000us-gaap_OilAndGasRevenue	$ 248,304,000us-gaap_OilAndGasRevenue	$ 1,390,228,000us-gaap_OilAndGasRevenue	$ 1,141,999,000us-gaap_OilAndGasRevenue	$ 686,668,000us-gaap_OilAndGasRevenue
Operating income	15,924,000us-gaap_OperatingIncomeLoss	134,103,000us-gaap_OperatingIncomeLoss	166,545,000us-gaap_OperatingIncomeLoss	329,080,000us-gaap_OperatingIncomeLoss	122,133,000us-gaap_OperatingIncomeLoss	150,862,000us-gaap_OperatingIncomeLoss	113,450,000us-gaap_OperatingIncomeLoss	117,953,000us-gaap_OperatingIncomeLoss	645,652,000us-gaap_OperatingIncomeLoss	504,398,000us-gaap_OperatingIncomeLoss	276,993,000us-gaap_OperatingIncomeLoss
Other income (expense)									168,816,000us-gaap_NonoperatingIncomeExpense	(141,381,000)us-gaap_NonoperatingIncomeExpense	(31,119,000)us-gaap_NonoperatingIncomeExpense
Income before income taxes									814,468,000	363,017,000	245,874,000
Total assets	5,938,412,000us-gaap_Assets				4,711,924,000us-gaap_Assets				5,938,412,000us-gaap_Assets	4,711,924,000us-gaap_Assets
Depreciation, depletion and amortization									412,334,000	307,055,000	206,734,000
Impairment of oil and gas properties									47,238,000us-gaap_ImpairmentOfOilAndGasProperties	1,168,000us-gaap_ImpairmentOfOilAndGasProperties	3,581,000us-gaap_ImpairmentOfOilAndGasProperties
Exploration and Production [Member]
Segment Reporting Information [Line Items]
Total revenues									1,304,004,000	1,084,412,000	670,491,000
Well Services [Member]
Segment Reporting Information [Line Items]
Total revenues									267,384,000	180,686,000	82,481,000
Midstream Services [Member]
Segment Reporting Information [Line Items]
Total revenues									50,958,000	29,230,000
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues									1,390,228,000	1,141,999,000	686,668,000
Operating income									645,652,000	504,398,000	276,993,000
Other income (expense)									168,816,000	(141,381,000)	(31,119,000)
Income before income taxes									814,468,000	363,017,000	245,874,000
Total assets	5,938,412,000				4,711,924,000				5,938,412,000	4,711,924,000	2,528,794,000
Capital expenditures									1,572,593,000	2,506,298,000	1,148,573,000
Depreciation, depletion and amortization									412,334,000	307,055,000	206,734,000
Impairment of oil and gas properties									47,238,000
Operating Segments [Member] \| Exploration and Production [Member]
Segment Reporting Information [Line Items]
Total revenues									1,304,004,000	1,084,412,000	670,491,000
Operating income									610,850,000	473,178,000	276,740,000
Other income (expense)									168,741,000	(141,397,000)	(31,120,000)
Income before income taxes									779,591,000	331,781,000	245,620,000
Total assets	5,802,295,000				4,592,140,000				5,802,295,000	4,592,140,000	2,493,364,000
Capital expenditures									1,525,168,000	2,514,737,000	1,150,439,000
Depreciation, depletion and amortization									406,960,000	304,388,000	206,127,000
Impairment of oil and gas properties									47,238,000
Operating Segments [Member] \| Well Services [Member]
Segment Reporting Information [Line Items]
Total revenues									74,610,000	51,845,000	16,177,000
Operating income									70,878,000	56,322,000	17,798,000
Other income (expense)									75,000	16,000	1,000
Income before income taxes									70,953,000	56,338,000	17,799,000
Total assets	281,844,000				78,359,000				281,844,000	78,359,000	63,875,000
Capital expenditures									37,292,000	15,217,000	15,679,000
Depreciation, depletion and amortization									14,080,000	7,150,000	2,694,000
Operating Segments [Member] \| Midstream Services [Member]
Segment Reporting Information [Line Items]
Total revenues									11,614,000	5,742,000
Operating income									22,730,000	17,509,000
Income before income taxes									22,730,000	17,509,000
Total assets	212,685,000				117,641,000				212,685,000	117,641,000
Capital expenditures									68,939,000	18,955,000
Depreciation, depletion and amortization									3,744,000	2,780,000
Segment Reconciling Items [Member] \| Well Services [Member]
Segment Reporting Information [Line Items]
Total revenues									192,774,000	128,841,000	66,304,000
Segment Reconciling Items [Member] \| Midstream Services [Member]
Segment Reporting Information [Line Items]
Total revenues									39,344,000	23,488,000
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenues									(232,118,000)	(152,329,000)	(66,304,000)
Operating income									(58,806,000)	(42,611,000)	(17,545,000)
Income before income taxes									(58,806,000)	(42,611,000)	(17,545,000)
Total assets	(358,412,000)				(76,216,000)				(358,412,000)	(76,216,000)	(28,445,000)
Capital expenditures									(58,806,000)	(42,611,000)	(17,545,000)
Depreciation, depletion and amortization									$ (12,450,000)	$ (7,263,000)	$ (2,087,000)