Segment Information (Details 2) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Operating segments information
Total assets	$ 7,720,194	$ 7,098,438
Reportable Segments
Operating segments information
Total assets	7,339,706	6,904,580
EQT Production
Operating segments information
Total assets	4,797,066	3,979,676
EQT Midstream
Operating segments information
Total assets	1,729,988	2,076,485
Distribution
Operating segments information
Total assets	812,652	848,419
Unallocated expenses
Operating segments information
Total assets	$ 380,488	$ 193,858