Derivative Instruments And Hedging Activities (Tables)

6 Months Ended

Jun. 30, 2012

Derivative Instruments And Hedging Activities [Abstract]

Volumes Under Derivative Contracts Related To Oil And Gas Producing Activities

Production Period	Instrument Type	Average Monthly Volumes	Weighted Average Price (1)
Crude Oil:			(per barrel)
July 2012 — December 2012..............	Collar	75.0 MBbl	$96.67 — $118.57 (2)
July 2012 — December 2012..............	Collar	99.1 MBbl	$99.67 — $118.42
July 2012 — December 2012..............	Swap	96.6 MBbl	$92.52
January 2013 — December 2013........	Swap	88.9 MBbl	$95.28
January 2013 — December 2013........	Collar	133.3 MBbl	$98.44 — $115.85
Natural Gas:			(per Mcf)
July 2012 — December 2012..............	Swap	777.5 Mmcf	$4.29
July 2012 — December 2012..............	Collar	156.7 Mmcf	$4.75 — $5.09
January 2013 — December 2013........	Swap	500.0 Mmcf	$4.09

a.The prices quoted in the table above are NYMEX Henry Hub for natural gas.Most of our oil contracts are indexed to the Brent crude oil price.

b.This contract is priced using NYMEX West Texas Intermediate for crude oil.

Derivatives Designated As Hedging Instruments

	As of June 30, 2012			As of December 31, 2011
	Balance Sheet Location		Fair Value	Balance Sheet Location		Fair Value
Asset Derivatives:
Natural gas contracts..........................	Other current assets	$	9,663	Other current assets	$	12,957
Oil contracts..........................................	Other current assets		16,033	Other current assets		8,567
Oil contracts..........................................	Other assets		5,737	Other assets		—
Natural gas contracts..........................	Other assets		1,239	Other assets		857
Interest rate swaps..............................	Other assets		—	Other assets		327
		$	32,672		$	22,708
	As of June 30, 2012			As of December 31, 2011
	Balance Sheet Location		Fair Value	Balance Sheet Location		Fair Value
Liability Derivatives:
Oil contracts..........................................	Accrued liabilities	$	5,324	Accrued liabilities	$	886
Interest rate swaps..............................	Accrued liabilities		317	Accrued liabilities		202
Oil contracts..........................................	Other long-term liabilities		1,059	Other long-term liabilities		1,711
Interest rate swaps..............................	Other long-term liabilities		59	Other long-term liabilities		—
		$	6,759		$	2,799

Derivatives Not Designated As Hedging Instruments

	As of June 30, 2012			As of December 31, 2011
	Balance Sheet Location		Fair Value	Balance Sheet Location		Fair Value
Asset Derivatives:
Foreign exchange forwards..........	Other current assets	$	—	Other current assets	$	55
		$	—		$	55
	As of June 30, 2012			As of December 31, 2011
	Balance Sheet Location		Fair Value	Balance Sheet Location		Fair Value
Liability Derivatives:
Foreign exchange forwards..........	Accrued liabilities	$	44	Accrued liabilities	$	159
		$	44		$	159

Impact Of Derivative Instruments On Accumulated Comprehensive Income (Loss)

		Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)
		Three Months Ended June 30,					Six Months Ended June 30,
		2012			2011		2012			2011
		(in thousands)
Oil and natural gas commodity contracts...	$	12,759		$	20,720	$	(796	)	$	9,942
Interest rate swaps.........................................		(79	)		250		(326	)		461
	$	12,680		$	20,970	$	(1,122	)	$	10,403

Gain (Loss) Reclassified From Accumulated OCI Into Income

				Gain (Loss) Reclassified from Accumulated OCI
				into Income
	Location of Gain (Loss)			(Effective Portion)
	Reclassified from			Three Months Ended						Six Months Ended
	Accumulated OCI into Income			June 30,						June 30,
	(Effective Portion)			2012			2011			2012			2011
			(in thousands)
Oil and natural gas commodity contracts..........................................	Oil and gas revenue	$		8,023		$	(11,860	)	$	8,132		$	(18,185	)
Interest rate swaps........................	Net interest expense			(120	)		(591	)		(313	)		(1,071	)
		$		7,903		$	(12,451	)	$	7,819		$	(19,256	)

Impact Of Non Designated Derivative Instruments On Income Statement

				Gain (Loss) Recognized in Income on Derivatives
	Location of Gain (Loss)			Three Months Ended					Six Months Ended
	Recognized in Income on			June 30,					June 30,
	Derivatives			2012			2011		2012		2011
			(in thousands)
Foreign exchange forwards	Other expense	$		(69	)	$	6	$	164	$	614
		$		(69	)	$	6	$	164	$	614