Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2011

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Instruments (Tables)

The location and fair value of the Company's derivative instruments on the Consolidated Balance Sheets were as follows:

Asset Derivatives	Location on Consolidated Balance Sheets	Fair Value at December 31, 2011		Fair Value at December 31, 2010
		(In thousands)
Designated as hedges:
Commodity derivatives	Commodity derivative instruments	$	27,687	$	15,123
	Other assets - noncurrent	2,768		4,104
		30,455		19,227
Not designated as hedges:
Commodity derivatives	Commodity derivative instruments	—		—
	Other assets - noncurrent	—		—
		—		—
Total asset derivatives		$	30,455	$	19,227

Liability Derivatives	Location on Consolidated Balance Sheets	Fair Value at December 31, 2011		Fair Value at December 31, 2010
		(In thousands)
Designated as hedges:
Commodity derivatives	Commodity derivative instruments	$	12,727	$	15,069
	Other liabilities - noncurrent	937		6,483
Interest rate derivatives	Other accrued liabilities	827		—
	Other liabilities - noncurrent	3,935		—
		18,426		21,552
Not designated as hedges:
Commodity derivatives	Commodity derivative instruments	437		9,359
	Other liabilities - noncurrent	—		—
		437		9,359
Total liability derivatives		$	18,863	$	30,911