Crude Oil and Natural Gas Property Information - Schedule of Results of Operations from Crude Oil and Natural Gas Producing Activities (Detail) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Crude oil and natural gas sales					$ 4,678,722		$ 2,982,966	$ 2,026,958
Production expenses					(390,423)		(324,214)	(289,289)
Production taxes					(353,140)		(208,278)	(142,388)
Results of Operations, Transportation Costs	$ (49,000)	$ (46,000)	$ (47,300)	$ (49,300)	(191,587)		0	0
Exploration Expense					(7,642)		(12,393)	(16,972)
Depreciation, depletion, amortization and accretion					(1,839,241)		(1,652,180)	(1,679,485)
Property impairments					(125,210)		(237,370)	(237,292)
Income tax (provision) benefit (2)					(434,047)	[1]	504,475	126,794
Results from crude oil and natural gas producing activities					$ 1,337,432		$ 1,053,006	$ (211,674)

[1] Income taxes reflect the application of a combined federal and state tax rate of 24.5% for 2018 and 38% for both 2017 and 2016 on pre-tax income and losses generated by operations in the United States. Additionally, the 2017 period includes a $713.7 million income tax benefit recognized upon the Company’s remeasurement of its deferred income tax assets and liabilities in response to the enactment of the Tax Cuts and Jobs Act in December 2017. See Note 9. Income Taxes for further discussion.