Financial Information by Business Segment (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating segments information
Total assets	$ 9,792,053	$ 8,849,862
Operating segments
Operating segments information
Total assets	8,873,494	7,722,092
Operating segments | EQT Production
Operating segments information
Total assets	6,359,065	5,675,534	5,256,600
Operating segments | EQT Midstream
Operating segments information
Total assets	2,514,429	2,046,558	1,785,100
Headquarters
Operating segments information
Total assets	$ 918,559	$ 1,127,770