CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Operating activities:
Net earnings (loss)	$ 33,439		$ (511,173)	$ (34,509)	$ (543,846)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion, and amortization	43,804		72,987	92,347	139,957
Deferred income tax				0	167,880
Unrealized losses (gains) on derivative instruments, net				15,398	(5,423)
Ceiling test write-down of oil and natural gas properties	0	34,800	348,976	0	383,793
Loss on debt extinguishment	0		0	25,223	0
Other, net				9,382	17,090
Changes in operating assets and liabilities:
Accounts receivable				(4,168)	19,077
Other current assets				(269)	2,305
Accounts payable and accrued liabilities				17,956	(20,601)
Accrued interest and other				(10,948)	16,192
Net cash provided by operating activities				110,412	176,424
Investing activities:
Capital expenditures for property and equipment				(206,214)	(400,691)
Proceeds from sales of assets				338,977	1,102
Net cash provided (used) by investing activities				132,763	(399,589)
Financing activities:
Proceeds from bank borrowings				320,000	443,000
Repayments of bank borrowings				(255,000)	(200,000)
Redemption of senior notes				(321,327)	0
Change in bank overdrafts				13,523	(20,666)
Net activity in investments from subsidiaries				0	0
Other, net				(1,006)	(1,501)
Net cash (used) provided by financing activities				(243,810)	220,833
Net decrease in cash and cash equivalents				(635)	(2,332)
Cash and cash equivalents at beginning of period		1,056		1,056	3,012
Cash and cash equivalents at end of period	421		680	421	680
Parent Company Net of Eliminations
Operating activities:
Net earnings (loss)				(52,817)	(536,247)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion, and amortization				70,678	101,403
Deferred income tax				0	150,397
Unrealized losses (gains) on derivative instruments, net				14,961	(3,649)
Ceiling test write-down of oil and natural gas properties				0	348,976
Loss on debt extinguishment				25,223	0
Other, net				11,384	17,896
Changes in operating assets and liabilities:
Accounts receivable				(10,086)	11,522
Other current assets				(390)	2,360
Accounts payable and accrued liabilities				18,865	(19,765)
Accrued interest and other				(10,697)	16,210
Net cash provided by operating activities				67,121	89,103
Investing activities:
Capital expenditures for property and equipment				(169,741)	(312,214)
Proceeds from sales of assets				338,975	1,102
Net cash provided (used) by investing activities				169,234	(311,112)
Financing activities:
Proceeds from bank borrowings				320,000	443,000
Repayments of bank borrowings				(255,000)	(200,000)
Redemption of senior notes				(321,327)	0
Change in bank overdrafts				13,932	(20,445)
Net activity in investments from subsidiaries				6,637	(203)
Other, net				(1,006)	(1,501)
Net cash (used) provided by financing activities				(236,764)	220,851
Net decrease in cash and cash equivalents				(409)	(1,158)
Cash and cash equivalents at beginning of period		667		667	1,734
Cash and cash equivalents at end of period	258		576	258	576
Guarantor Subsidiary
Operating activities:
Net earnings (loss)	16,923		11,189	23,271	31,008
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion, and amortization	9,560		19,015	20,408	37,683
Deferred income tax				0	19,917
Unrealized losses (gains) on derivative instruments, net				433	(1,751)
Ceiling test write-down of oil and natural gas properties	0		0	0	0
Loss on debt extinguishment				0	0
Other, net				205	187
Changes in operating assets and liabilities:
Accounts receivable				4,507	7,641
Other current assets				3	(1)
Accounts payable and accrued liabilities				(541)	(1,254)
Accrued interest and other				(187)	96
Net cash provided by operating activities				48,099	93,526
Investing activities:
Capital expenditures for property and equipment				(35,699)	(80,990)
Proceeds from sales of assets				0	0
Net cash provided (used) by investing activities				(35,699)	(80,990)
Financing activities:
Proceeds from bank borrowings				0	0
Repayments of bank borrowings				0	0
Redemption of senior notes				0	0
Change in bank overdrafts				(457)	(341)
Net activity in investments from subsidiaries				(11,987)	(12,194)
Other, net				0	0
Net cash (used) provided by financing activities				(12,444)	(12,535)
Net decrease in cash and cash equivalents				(44)	1
Cash and cash equivalents at beginning of period		45		45	1
Cash and cash equivalents at end of period	1		2	1	2
Combined Non-Guarantor Subsidiaries
Operating activities:
Net earnings (loss)	(2,761)		(1,994)	(4,963)	(38,607)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion, and amortization	1,128		438	1,261	871
Deferred income tax				0	(2,434)
Unrealized losses (gains) on derivative instruments, net				4	(23)
Ceiling test write-down of oil and natural gas properties	0		0	0	34,817
Loss on debt extinguishment				0	0
Other, net				(2,207)	(993)
Changes in operating assets and liabilities:
Accounts receivable				1,411	(86)
Other current assets				118	(54)
Accounts payable and accrued liabilities				(368)	418
Accrued interest and other				(64)	(114)
Net cash provided by operating activities				(4,808)	(6,205)
Investing activities:
Capital expenditures for property and equipment				(774)	(7,487)
Proceeds from sales of assets				2	0
Net cash provided (used) by investing activities				(772)	(7,487)
Financing activities:
Proceeds from bank borrowings				0	0
Repayments of bank borrowings				0	0
Redemption of senior notes				0
Change in bank overdrafts				48	120
Net activity in investments from subsidiaries				5,350	12,397
Other, net				0	0
Net cash (used) provided by financing activities				5,398	12,517
Net decrease in cash and cash equivalents				(182)	(1,175)
Cash and cash equivalents at beginning of period		344		344	1,277
Cash and cash equivalents at end of period	$ 162		$ 102	$ 162	$ 102