Income Taxes (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income tax expense from continuing operations
Current income tax expense (benefit)			$ 75	$ (10,984)
Deferred income tax expense (benefit)		$ (128,857)	(295,126)	(485,392)
Total income tax expense from continuing operations		$ (128,857)	$ (295,051)	$ (496,376)
U.S. Statutory federal income tax rate (as a percent)	21.00%	21.00%	35.00%	35.00%
Reconciliation of income tax expense from continuing operations differs from the amount that would be computed by applying the U.S. statutory federal income tax rate to consolidated income
Federal income tax expense		$ (36,657)	$ 171,530	$ (436,038)
State income tax expense , net of federal benefit		(12,627)	10,779	(20,364)
Change in Federal tax rate, net of state benefit			(427,962)
Change in State tax rate, net of federal effect		(40,415)
Nondeductible stock compensation		6,079	12,098	3,691
Noncontrolling interest in Antero Midstream Partners LP		(73,881)	(59,523)	(34,780)
Change in valuation allowance		28,116	(2,073)	(10,852)
Other		528	100	1,967
Total income tax expense from continuing operations		(128,857)	(295,051)	(496,376)
Income tax expense (benefit) allocated to continuing and discontinued operations
Total income tax expense from continuing operations		(128,857)	(295,051)	$ (496,376)
Deferred tax assets:
Net operating loss carryforwards		734,255	727,522
Equity based compensation		10,633	12,062
Investment in Antero Midstream Partners LP			38,613
Other		15,726	11,236
Total deferred tax assets		760,614	789,433
Valuation allowance		(45,477)	(17,361)
Net deferred tax assets		715,137	772,072
Deferred tax liabilities:
Unrealized gains on derivative instruments		271,747	442,855
Oil and gas properties		1,055,850	1,058,543
Investment in Antero Midstream Partners LP		11,258
Other		27,070	50,319
Total deferred tax liabilities		1,365,925	1,551,717
Net deferred tax liabilities		(650,788)	(779,645)
State
Deferred tax liabilities:
Valuation allowance on net operating loss carryforwards		$ 45,000	$ 17,000