Interim Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Total operating revenues	$ 1,011,483	$ 951,576	$ 1,310,252	$ 1,143,173	$ 1,245,138	$ 1,050,046	$ 950,648	$ 1,312,036	$ 4,416,484	$ 4,557,868	$ 3,091,020
Operating income (loss)	(1,462,067)	(161,529)	296,030	175,456	(570,691)	(147,451)	(114,650)	(1,950,332)	(1,152,110)	(2,783,124)	382,212
Amounts attributable to EQT Corporation:
(Loss) income from continuing operations					(598,062)	(127,347)	(76,978)	(1,578,533)	(1,221,695)	(2,380,920)	1,387,029
Income from discontinued operations, net of tax					(38,625)	87,654	94,784	(7,461)	0	136,352	121,500
Net (loss) income attributable to EQT Corporation	$ (1,176,924)	$ (361,028)	$ 125,566	$ 190,691	$ (636,687)	$ (39,693)	$ 17,806	$ (1,585,994)	(1,221,695)	(2,244,568)	1,508,529
Basic and diluted:
(Loss) income from continuing operations (in dollars per share)					$ (2.35)	$ (0.49)	$ (0.29)	$ (5.96)
Income from discontinued operations (in dollars per share)					(0.15)	0.34	0.36	(0.03)
Basic and diluted net income (loss) (in dollars per share)	$ (4.61)	$ (1.41)	$ 0.49	$ 0.75	$ (2.50)	$ (0.15)	$ 0.07	$ (5.99)
Impairment/loss on sale/exchange of long-lived assets	$ 1,124,400								$ 1,138,287	$ 2,709,976	$ 0