Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Schedule of deferred tax assets and liabilities

Significant components of net deferred tax assets (liabilities) at December 31, 2012 and 2011 are as follows:



	2012			2011
	(In thousands)
Deferred tax assets:
Net operating loss carryforwards	$	122,393		$	54,124
Fair value of derivatives	—			1,958
Statutory depletion carryforwards	8,159			7,359
Asset retirement obligations and other	21,814			21,165
	152,366			84,606
Deferred tax liabilities:
Fair value of derivatives	(4,208		)	—
Property and equipment	(295,428		)	(209,867		)
	(299,636		)	(209,867		)
Net deferred tax liabilities	$	(147,270	)	$	(125,261	)

Components of net deferred tax liabilities:
Current assets	$	8,560		$	8,948
Non-current liabilities	(155,830		)	(134,209		)
Net deferred tax liabilities	$	(147,270	)	$	(125,261	)

Schedule of effective income tax rate reconciliation

For the years ended December 31, 2012, 2011 and 2010, effective income tax rates were different than the statutory federal income tax rates for the following reasons:



	2012			2011			2010
	(In thousands)
Income tax expense at statutory rate of 35%	$	19,989		$	50,921		$	20,150
Tax depletion in excess of basis	(581		)	(425		)	(490		)
Revision of previous tax estimates	700			217			8
State income taxes, net of federal tax effect	1,513			1,310			884
Other	387			119			82
Income tax expense	$	22,008		$	52,142		$	20,634
Current	$	—		$	(408	)	$	375
Deferred	22,008			52,550			20,259
Income tax expense	$	22,008		$	52,142		$	20,634