CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Details 3) (USD $) In Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Revenues:
Oil, natural gas, and natural gas liquids sales	$ 237,848	$ 207,954	$ 440,419	$ 429,683
Interest and other	286	141	850	277
Total revenues	238,134	208,095	441,269	429,960
Costs, expenses, and other:
Lease operating expenses	32,463	28,422	64,320	57,524
Other direct operating costs	21,083	18,507	40,568	34,794
General and administrative	15,737	17,781	34,771	36,534
Depreciation, depletion, and amortization	73,322	62,446	140,885	114,758
Interest expense	38,842	37,109	76,722	75,152
Realized and unrealized losses (gains) on derivative instruments, net	(46,047)	(25,031)	(9,801)	(118,242)
Other, net	12,052	14,549	8,169	6,555
Total costs, expenses, and other	147,452	153,783	355,634	207,075
Earnings before income taxes	90,682	54,312	85,635	222,885
Income tax	51,708	21,058	49,991	80,469
Net earnings	38,974	33,254	35,644	142,416
Less: net earnings attributable to noncontrolling interest	64		64
Net earnings attributable to Forest Oil Corporation	38,910	33,254	35,580	142,416
Parent Company
Revenues:
Oil, natural gas, and natural gas liquids sales	136,349	116,748	253,362	259,204
Interest and other	541	1,083	1,348	2,767
Equity earnings (losses) in subsidiaries	20,341	18,186	45,888	59,253
Total revenues	157,231	136,017	300,598	321,224
Costs, expenses, and other:
Lease operating expenses	19,733	19,486	40,269	40,117
Other direct operating costs	13,198	11,894	25,344	23,118
General and administrative	10,922	14,412	26,610	30,060
Depreciation, depletion, and amortization	38,989	32,607	75,063	63,490	0
Interest expense	36,516	35,331	73,016	72,634
Realized and unrealized losses (gains) on derivative instruments, net	(39,968)	(21,014)	(4,172)	(98,061)
Other, net	7,793	1,577	10,249	(1,127)
Total costs, expenses, and other	87,183	94,293	246,379	130,231
Earnings before income taxes	70,048	41,724	54,219	190,993
Income tax	31,138	8,470	18,639	48,577
Net earnings	38,910	33,254	35,580	142,416
Net earnings attributable to Forest Oil Corporation	38,910	33,254	35,580	142,416
Guarantor Subsidiary
Revenues:
Oil, natural gas, and natural gas liquids sales	49,530	52,353	98,246	93,495
Interest and other	6		62	9
Total revenues	49,536	52,353	98,308	93,504
Costs, expenses, and other:
Lease operating expenses	3,640	2,937	6,628	5,626
Other direct operating costs	2,837	3,615	5,923	6,229
General and administrative	604	615	1,213	1,163
Depreciation, depletion, and amortization	12,850	13,096	24,942	20,905	0
Interest expense	(124)	221	(192)	1,078
Realized and unrealized losses (gains) on derivative instruments, net	(903)	(3,987)	(498)	(19,941)
Other, net	20	84	(21)	32
Total costs, expenses, and other	18,924	16,581	37,995	15,092
Earnings before income taxes	30,612	35,772	60,313	78,412
Income tax	13,699	13,132	22,672	28,918
Net earnings	16,913	22,640	37,641	49,494
Net earnings attributable to Forest Oil Corporation	16,913	22,640	37,641	49,494
Combined Non-Guarantor Subsidiaries
Revenues:
Oil, natural gas, and natural gas liquids sales	51,969	38,853	88,811	76,984
Interest and other	8	3	20	9
Total revenues	51,977	38,856	88,831	76,993
Costs, expenses, and other:
Lease operating expenses	9,090	5,999	17,423	11,781
Other direct operating costs	5,048	2,998	9,301	5,447
General and administrative	4,211	2,754	6,948	5,311
Depreciation, depletion, and amortization	21,483	16,743	40,880	30,363	0
Interest expense	2,719	2,502	4,478	3,948
Realized and unrealized losses (gains) on derivative instruments, net	(5,176)	(30)	(5,131)	(240)
Other, net	4,239	12,888	(2,059)	7,650
Total costs, expenses, and other	41,614	43,854	71,840	64,260
Earnings before income taxes	10,363	(4,998)	16,991	12,733
Income tax	6,871	(544)	8,680	2,974
Net earnings	3,492	(4,454)	8,311	9,759
Less: net earnings attributable to noncontrolling interest	64		64
Net earnings attributable to Forest Oil Corporation	3,428	(4,454)	8,247	9,759
Elimination
Revenues:
Interest and other	(269)	(945)	(580)	(2,508)
Equity earnings (losses) in subsidiaries	(20,341)	(18,186)	(45,888)	(59,253)
Total revenues	(20,610)	(19,131)	(46,468)	(61,761)
Costs, expenses, and other:
Depreciation, depletion, and amortization					0
Interest expense	(269)	(945)	(580)	(2,508)
Total costs, expenses, and other	(269)	(945)	(580)	(2,508)
Earnings before income taxes	(20,341)	(18,186)	(45,888)	(59,253)
Net earnings	(20,341)	(18,186)	(45,888)	(59,253)
Net earnings attributable to Forest Oil Corporation	$ (20,341)	$ (18,186)	$ (45,888)	$ (59,253)