CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Operating activities:
Net earnings (loss)	$ (458,552)			$ 87,718	$ (1,002,398)	$ 123,362
Less: net earnings from discontinued operations	0			28,108	0	44,569
Net earnings (loss) from continuing operations	(458,552)			59,610	(1,002,398)	78,793
Adjustments to reconcile net earnings (loss) from continuing operations to net cash provided (used) by operating activities of continuing operations:
Depreciation, depletion, and amortization	73,845			54,323	213,802	155,227
Deferred income tax					208,990	46,724
Unrealized losses (gains) on derivative instruments, net					46,372	(40,538)
Ceiling test write-down of oil and natural gas properties	329,957	349,000	34,800	0	713,750	0
Impairment of properties	79,529			0	79,529	0
Other, net					23,579	28,379
Changes in operating assets and liabilities:
Accounts receivable					9,070	29,686
Other current assets					4,426	8,262
Accounts payable and accrued liabilities					2,182	(5,096)
Accrued interest and other					(13,477)	3,977
Net cash provided by operating activities of continuing operations					285,825	305,414
Investing activities:
Capital expenditures for property and equipment					(604,893)	(661,264)
Proceeds from sales of assets					8,902	120,956
Net cash used by investing activities of continuing operations					(595,991)	(540,308)
Financing activities:
Proceeds from bank borrowings					651,000	12,000
Repayments of bank borrowings					(756,000)	(12,000)
Issuance of senior notes, net of issuance costs					491,250	0
Change in bank overdrafts					(37,716)	(20,660)
Net activity in investments from subsidiaries					0	0
Other, net					(2,211)	(12,307)
Net cash provided (used) by financing activities of continuing operations					346,323	(32,967)
Cash flows of discontinued operations:
Operating cash flows					0	101,292
Investing cash flows					0	(255,470)
Financing cash flows					0	478,324
Net cash provided by discontinued operations					0	324,146
Effect of exchange rate changes on cash					0	(3,476)
Net increase in cash and cash equivalents					36,157	52,809
Net increase in cash and cash equivalents of discontinued operations					0	(289)
Net increase in cash and cash equivalents of continuing operations					36,157	52,520
Cash and cash equivalents of continuing operations at beginning of period			3,012		3,012	217,569
Cash and cash equivalents of continuing operations at end of period	39,169			270,089	39,169	270,089
Parent Company Net of Eliminations
Operating activities:
Net earnings (loss)					(921,087)	32,534
Less: net earnings from discontinued operations					0	0
Net earnings (loss) from continuing operations					(921,087)	32,534
Adjustments to reconcile net earnings (loss) from continuing operations to net cash provided (used) by operating activities of continuing operations:
Depreciation, depletion, and amortization					157,381	115,738
Deferred income tax					199,415	18,540
Unrealized losses (gains) on derivative instruments, net					37,698	(45,114)
Ceiling test write-down of oil and natural gas properties					673,131	0
Impairment of properties					0	0
Other, net					25,311	30,018
Changes in operating assets and liabilities:
Accounts receivable					4,657	12,168
Other current assets					4,463	6,756
Accounts payable and accrued liabilities					1,915	(7,118)
Accrued interest and other					(13,102)	3,420
Net cash provided by operating activities of continuing operations					169,782	166,942
Investing activities:
Capital expenditures for property and equipment					(496,178)	(501,683)
Proceeds from sales of assets					8,902	120,949
Net cash used by investing activities of continuing operations					(487,276)	(380,734)
Financing activities:
Proceeds from bank borrowings					651,000	12,000
Repayments of bank borrowings					(756,000)	(12,000)
Issuance of senior notes, net of issuance costs					491,250	0
Change in bank overdrafts					(37,661)	(20,979)
Net activity in investments from subsidiaries					8,480	299,883
Other, net					(2,211)	(12,307)
Net cash provided (used) by financing activities of continuing operations					354,858	266,597
Cash flows of discontinued operations:
Operating cash flows					0	0
Investing cash flows					0	0
Financing cash flows					0	0
Net cash provided by discontinued operations					0	0
Effect of exchange rate changes on cash					0	0
Net increase in cash and cash equivalents					37,364	52,805
Net increase in cash and cash equivalents of discontinued operations					0	0
Net increase in cash and cash equivalents of continuing operations					37,364	52,805
Cash and cash equivalents of continuing operations at beginning of period			1,734		1,734	216,580
Cash and cash equivalents of continuing operations at end of period	39,098			269,385	39,098	269,385
Guarantor Subsidiary
Operating activities:
Net earnings (loss)	10,320			12,415	41,328	50,056
Less: net earnings from discontinued operations	0			0	0	0
Net earnings (loss) from continuing operations	10,320			12,415	41,328	50,056
Adjustments to reconcile net earnings (loss) from continuing operations to net cash provided (used) by operating activities of continuing operations:
Depreciation, depletion, and amortization	17,433			13,251	55,116	38,193
Deferred income tax					19,075	30,497
Unrealized losses (gains) on derivative instruments, net					8,565	4,566
Ceiling test write-down of oil and natural gas properties	0			0	0	0
Impairment of properties	0			0	0	0
Other, net					294	243
Changes in operating assets and liabilities:
Accounts receivable					7,164	16,341
Other current assets					(6)	443
Accounts payable and accrued liabilities					(1,330)	787
Accrued interest and other					143	(122)
Net cash provided by operating activities of continuing operations					130,349	141,004
Investing activities:
Capital expenditures for property and equipment					(99,814)	(89,477)
Proceeds from sales of assets					0	0
Net cash used by investing activities of continuing operations					(99,814)	(89,477)
Financing activities:
Proceeds from bank borrowings					0	0
Repayments of bank borrowings					0	0
Issuance of senior notes, net of issuance costs					0	0
Change in bank overdrafts					(213)	185
Net activity in investments from subsidiaries					(30,323)	(51,715)
Other, net					0	0
Net cash provided (used) by financing activities of continuing operations					(30,536)	(51,530)
Cash flows of discontinued operations:
Operating cash flows					0	0
Investing cash flows					0	0
Financing cash flows					0	0
Net cash provided by discontinued operations					0	0
Effect of exchange rate changes on cash					0	0
Net increase in cash and cash equivalents					(1)	(3)
Net increase in cash and cash equivalents of discontinued operations					0	0
Net increase in cash and cash equivalents of continuing operations					(1)	(3)
Cash and cash equivalents of continuing operations at beginning of period			1		1	3
Cash and cash equivalents of continuing operations at end of period	0			0	0	0
Combined Non-Guarantor Subsidiaries
Operating activities:
Net earnings (loss)	(84,032)			26,678	(122,639)	40,772
Less: net earnings from discontinued operations	0			28,108	0	44,569
Net earnings (loss) from continuing operations	(84,032)			(1,430)	(122,639)	(3,797)
Adjustments to reconcile net earnings (loss) from continuing operations to net cash provided (used) by operating activities of continuing operations:
Depreciation, depletion, and amortization	434			397	1,305	1,296
Deferred income tax					(9,500)	(2,313)
Unrealized losses (gains) on derivative instruments, net					109	10
Ceiling test write-down of oil and natural gas properties	5,802			0	40,619	0
Impairment of properties	79,529			0	79,529	0
Other, net					(2,026)	(1,882)
Changes in operating assets and liabilities:
Accounts receivable					(2,751)	1,177
Other current assets					(31)	1,063
Accounts payable and accrued liabilities					1,597	1,235
Accrued interest and other					(518)	679
Net cash provided by operating activities of continuing operations					(14,306)	(2,532)
Investing activities:
Capital expenditures for property and equipment					(8,901)	(70,104)
Proceeds from sales of assets					0	7
Net cash used by investing activities of continuing operations					(8,901)	(70,097)
Financing activities:
Proceeds from bank borrowings					0	0
Repayments of bank borrowings					0	0
Issuance of senior notes, net of issuance costs					0	0
Change in bank overdrafts					158	134
Net activity in investments from subsidiaries					21,843	(248,168)
Other, net					0	0
Net cash provided (used) by financing activities of continuing operations					22,001	(248,034)
Cash flows of discontinued operations:
Operating cash flows					0	101,292
Investing cash flows					0	(255,470)
Financing cash flows					0	478,324
Net cash provided by discontinued operations					0	324,146
Effect of exchange rate changes on cash					0	(3,476)
Net increase in cash and cash equivalents					(1,206)	7
Net increase in cash and cash equivalents of discontinued operations					0	(289)
Net increase in cash and cash equivalents of continuing operations					(1,206)	(282)
Cash and cash equivalents of continuing operations at beginning of period			1,277		1,277	986
Cash and cash equivalents of continuing operations at end of period	$ 71			$ 704	$ 71	$ 704