Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Revenues and other income:
Oil and gas	$ 3,155,696		$ 2,575,311	$ 2,080,215
Sales of purchased oil and gas	333,822		122,093	14,542
Interest and other	16,961		(1,032)	29,382
Derivative gains, net	4,010		330,251	392,752
Gain (Loss) on disposition of assets, net	209,021		45,898	(3,644)
Revenues and other income	3,719,510		3,072,521	2,513,247
Costs and expenses:
Oil and gas production	614,676		558,045	396,961
Production and ad valorem taxes	201,186		178,723	139,425
Depletion, depreciation and amortization	907,077		708,270	489,579
Purchased oil and gas	335,734		120,408	13,949
Impairment of oil and gas properties	1,495,242		0	354,408
Exploration and abandonments	98,448		98,285	80,691
General and administrative	295,868		244,196	189,985
Accretion of discount on asset retirement obligations	11,862		8,677	7,506
Interest	183,750		204,222	181,604
Other	137,386		114,175	63,071
Costs and expenses, Total	4,281,229		2,235,001	1,917,179
Income (loss) from continuing operations before income taxes	(561,719)		837,520	596,068
Income tax benefit (provision)	211,775		(290,488)	(188,278)
Income (loss) from continuing operations	(349,944)		547,032	407,790
Income (loss) from discontinued operations, net of tax	(449,605)		(304,210)	474,124
Net income (loss)	(799,549)		242,822	881,914
Net income attributable to noncontrolling interests	(38,865)		(50,537)	(47,425)
Net income (loss) attributable to common stockholders	(838,414)		192,285	834,489
Basic earnings per share:
Income (loss) from continuing operations attributable to common stockholders	$ (2.86)		$ 4.02	$ 3.03
Income (loss) from discontinued operations attributable to common stockholders	$ (3.30)		$ (2.48)	$ 3.98
Net income (loss) attributable to common stockholders	$ (6.16)		$ 1.54	$ 7.01
Diluted earnings per share:
Income (loss) from continuing operations attributable to common stockholders	$ (2.86)		$ 3.91	$ 2.97
Income (loss) from discontinued operations attributable to common stockholders	$ (3.30)		$ (2.41)	$ 3.91
Net income (loss) attributable to common stockholders	$ (6.16)		$ 1.50	$ 6.88
Weighted average shares outstanding:
Basic	136,130	[1]	122,966	116,904
Diluted	136,130	[1]	126,320	119,215
Amounts attributable to common stockholders:
Income (loss) from continuing operations, net of tax	(388,809)		496,495	360,365
Income (loss) from discontinued operations, net of tax	(449,605)		(304,210)	474,124
Net income (loss)	$ (838,414)		$ 192,285	$ 834,489

[1] (a)The following common share equivalents were excluded from the weighted average diluted shares for the year ended December 31, 2013 because they would have been anti-dilutive to the loss recorded for the period: (i) 135,190 outstanding options to purchase the Company's common stock, (ii) 200,360 common shares attributable to unvested performance awards and (iii) 1,087,401 common shares related to the 2013 redemption of the Convertible Senior Notes, representing the weighted average portion of the year that is not included in the basic weighted average common shares outstanding.