Consolidated Statements Of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net income	$ 609,504	$ 449,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depletion, depreciation and amortization	294,271	288,737
Exploration expenses, including dry holes	4,275	7,973
Hurricane activity, net		3,500
Deferred income taxes	75,507	220,352
(Gain) loss on disposition of assets, net	2,487	(24,588)
Accretion of discount on asset retirement obligations	5,313	5,388
Discontinued operations	(407,115)	41,463
Interest expense	15,432	14,920
Derivative related activity	56,380	(442,087)
Amortization of stock-based compensation	21,155	19,049
Amortization of deferred revenue	(22,290)	(45,070)
Other noncash items	(18,277)	1,324
Change in operating assets and liabilities
Accounts receivable, net	(23,605)	96,376
Income taxes receivable	27,226	23,440
Inventories	(74,136)	12,479
Prepaid expenses	(9,990)	(10,204)
Other current assets	8,772	(7,192)
Accounts payable	6,201	50,458
Interest payable	(1,642)	7,014
Income taxes payable	(11,485)	(4,470)
Other current liabilities	6,471	(14,943)
Net cash provided by operating activities	564,454	693,214
Cash flows from investing activities:
Proceeds from disposition of assets, net of cash sold	813,520	297,312
Investment in unconsolidated subsidiary	(82,857)	(108)
Additions to oil and gas properties	(757,148)	(461,502)
Additions to other assets and other property and equipment, net	(215,367)	(74,075)
Net cash used in investing activities	(241,852)	(238,373)
Cash flows from financing activities:
Borrowings under long-term debt	72,610	182,997
Principal payments on long-term debt	(115,810)	(424,107)
Contributions from noncontrolling interests		1,151
Distributions to noncontrolling interests	(13,366)	(13,451)
Payments of other liabilities	(305)	(20,325)
Exercise of long-term incentive plan stock options	362	3,452
Purchases of treasury stock	(39,218)	(13,402)
Excess tax benefits from share-based payment arrangements	27,937	4,090
Payment of financing fees	(8,739)	(145)
Dividends paid	(4,812)	(4,783)
Net cash used in financing activities	(81,341)	(284,523)
Net increase in cash and cash equivalents	241,261	170,318
Cash and cash equivalents, beginning of period	111,160	27,368
Cash and cash equivalents, end of period	$ 352,421	$ 197,686