CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flows From Operating Activities
Net income (loss)	$ 637,769	$ 603,833	$ (35,792)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	707,966	591,943	495,291
Impairment of natural gas and oil properties	0	0	907,812
Deferred income taxes	409,023	379,720	48,606
Unrealized (gain) loss on derivatives	(281)	(4,289)	5,309
Stock-based compensation expense	10,550	9,820	10,177
Other	991	(1,348)	9,625
Change in assets and liabilities:
Accounts receivable	9,659	(88,488)	(8,519)
Inventories	(12,975)	5,099	11,779
Accounts payable	11,490	65,782	(21,739)
Taxes payable	(9,360)	24,551	(6,451)
Interest payable	610	179	(1,082)
Advances from partners	2,377	29,299	(18,197)
Tax benefit for stock-based compensation	(14,626)	0	0
Other assets and liabilities	(13,376)	26,484	(37,443)
Net cash provided by operating activities	1,739,817	1,642,585	1,359,376
Cash Flows From Investing Activities
Capital investments	(2,184,474)	(2,073,174)	(1,780,165)
Proceeds from sale of property and equipment	154,526	350,227	818
Transfers to restricted cash	(85,055)	(356,035)	0
Transfers from restricted cash	85,055	356,035	0
Other	5,158	(2,684)	(1,257)
Net cash used in investing activities	(2,024,790)	(1,725,631)	(1,780,604)
Cash Flows From Financing Activities
Payments on current portion of long-term debt	(1,200)	(1,200)	(61,200)
Payments on revolving long-term debt	(3,445,900)	(2,958,100)	(1,371,700)
Borrowings under revolving long-term debt	3,696,200	3,054,800	1,696,200
Change in bank drafts outstanding	24,637	(11,545)	(30,920)
Revolving credit facility costs	(10,211)	0	0
Proceeds from exercise of common stock options	6,412	3,897	5,755
Tax benefit for stock-based compensation	14,626	0	0
Other	(261)	(1,612)	0
Net cash provided by financing activities	284,303	86,240	238,135
Effect of exchange rate changes on cash	242	(323)	0
Increase (Decrease) in cash and cash equivalents	(428)	2,871	(183,093)
Cash and cash equivalents at beginning of year	16,055	13,184	196,277
Cash and cash equivalents at end of year	$ 15,627	$ 16,055	$ 13,184