Derivative instruments (Tables)

9 Months Ended

Sep. 30, 2011

Derivative instruments [Abstract]

Schedule of Derivative Instruments by Balance Sheet Location and Fair Value Table

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

Asset Derivatives	Location on Consolidated Balance Sheets	Fair Value at September 30, 2011		Fair Value at September 30, 2010		Fair Value at December 31, 2010
		(In thousands)
Designated as hedges:
Commodity derivatives	Commodity derivative instruments	$	38,458	$	26,803	$	15,123
	Other assets - noncurrent		15,575		8,423		4,104
			54,033		35,226		19,227
Not designated as hedges:
Commodity derivatives	Commodity derivative instruments		336		-		-
Total asset derivatives		$	54,369	$	35,226	$	19,227

Liability Derivatives	Location on Consolidated Balance Sheets	Fair Value at September 30, 2011		Fair Value at September 30, 2010		Fair Value at December 31, 2010
		(In thousands)
Designated as hedges:
Commodity derivatives	Commodity derivative instruments	$	1,723	$	4,649	$	15,069
	Other liabilities - noncurrent		157		1,845		6,483
Interest rate derivatives	Other liabilities - noncurrent		3,491		-		-
			5,371		6,494		21,552
Not designated as hedges:
Commodity derivatives	Commodity derivative instruments		1,305		21,154		9,359
	Other liabilities - noncurrent		-		418		-
			1,305		21,572		9,359
Total liability derivatives		$	6,676	$	28,066	$	30,911