Statements of Condensed Consolidated Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests in Consolidated Subsidiaries
Beginning Balance (in shares) at Dec. 31, 2013		150,884
Beginning Balance at Dec. 31, 2013	$ 4,864,128	$ 1,422,105	$ 2,567,980	$ 44,703	$ 829,340
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	349,199		303,114		46,085
Net change in cash flow hedges:
Natural gas, net of tax benefit of $55,211 and $27,880 during the 6 months ended June 30, 2015 and 2014, respectively	(41,238)			(41,238)
Interest rate, net of tax of $50 and $50 during the 6 months ended June 30, 2015 and 2014	72			72
Pension and other post-retirement benefits liability adjustment, net of tax of $255 and $227 during the 6 months ended June 30, 2015 and 2014	352			352
Dividends ($0.06 per share during 6 months ended June 30, 2015 and 2014, respectively)	(9,101)		(9,101)
Stock-based compensation plans, net (in shares)		918
Stock-based compensation plans, net	22,112	$ 20,973			1,139
Distributions to noncontrolling interests ($1.19 and $0.95 per common unit during the 6 months ended June 30, 2015 and 2014, respectively)	(25,674)				(25,674)
Issuance of common units of EQT Midstream Partners, LP	902,451				902,451
Repurchase and retirement of common stock (in shares)		(300)
Repurchase and retirement of common stock	(32,368)	$ (12,759)	(19,609)
Ending Balance (in shares) at Jun. 30, 2014		151,502
Ending Balance at Jun. 30, 2014	6,029,933	$ 1,430,319	2,842,384	3,889	1,753,341
Beginning Balance (in shares) at Dec. 31, 2014		151,596
Beginning Balance at Dec. 31, 2014	6,373,063	$ 1,466,192	2,917,129	199,494	1,790,248
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	284,915		178,963		105,952
Net change in cash flow hedges:
Natural gas, net of tax benefit of $55,211 and $27,880 during the 6 months ended June 30, 2015 and 2014, respectively	(83,332)			(83,332)
Interest rate, net of tax of $50 and $50 during the 6 months ended June 30, 2015 and 2014	72			72
Pension and other post-retirement benefits liability adjustment, net of tax of $255 and $227 during the 6 months ended June 30, 2015 and 2014	404			404
Dividends ($0.06 per share during 6 months ended June 30, 2015 and 2014, respectively)	(9,141)		(9,141)
Stock-based compensation plans, net (in shares)		846
Stock-based compensation plans, net	28,555	$ 28,006			549
Distributions to noncontrolling interests ($1.19 and $0.95 per common unit during the 6 months ended June 30, 2015 and 2014, respectively)	(52,672)				(52,672)
Issuance of common units of EQT Midstream Partners, LP	696,582				696,582
Sale of common units of EQT GP Holdings, LP	674,374				674,374
Changes in ownership of EQT Midstream Partners, LP	(72,954)	122,833			(195,787)
Changes in ownership of EQT GP Holdings, LP	(191,250)	$ 322,008			(513,258)
Repurchase and retirement of common stock (in shares)		(38)
Repurchase and retirement of common stock	(3,375)	$ (1,597)	(1,778)
Ending Balance (in shares) at Jun. 30, 2015		152,404
Ending Balance at Jun. 30, 2015	$ 7,645,241	$ 1,937,442	$ 3,085,173	$ 116,638	$ 2,505,988