Supplemental Gas Data Acreages (Details)	Dec. 31, 2013 acre
Gas and Oil Acreage [Line Items]
Productive Gas Wells, Number of Wells, Gross	15,063,000
Gas and Oil Acreage, Undeveloped, Net	59,346,000
unproved acreage gross	5,396,659,000
Gas and Oil Acreage, Unproved, Net	4,212,030,000
Total Acreage - Gross	6,044,066,000
Total Acreage - Net	4,799,069,000
Productive Gas Wells, Number of Wells, Net	12,874,000
Gas and Oil Area, Developed, Gross	542,388,000
Gas and Oil Area, Developed, Net	527,693,000
Gas and Oil Area, Undeveloped, Gross	105,019,000