Income Taxes (Tables)

12 Months Ended

Dec. 31, 2011

Income Taxes

Schedule of current and deferred federal and state income tax expense (benefit)

	2011		2010		2009
Current income tax expense (benefit)	$	128,209	$	39,554	$	(96,140	)
Deferred income tax expense		30,418		44,306		88,922
Total income tax expense (benefit)	$	158,627	$	83,860	$	(7,218	)

Schedule of reconciliation of statutory tax rates to actual effective tax rates

	2011			2010			2009
Statutory federal tax rate		35.0	%		35.0	%		35.0	%
State income taxes, net of federal benefit		3.5			3.2			1.9
Other permanent differences		(1.1	)		1.1			2.7
Effective tax rate		37.4	%		39.3	%		39.6	%

Schedule of components of deferred tax assets and liabilities

	2011			2010
Deferred tax assets
Capitalized start-up costs	$	29,182		$	29,728
Assets capitalized for tax, expensed for books		32,711			28,017
Accrued expenses		31,824			26,122
Total deferred tax assets		93,717			83,867
Deferred tax liabilities
Property, plant and equipment		(471,847	)		(448,557	)
Intangible assets		(79,778	)		(69,455	)
Other		(6,666	)		(2,603	)
Total deferred tax liabilities		(558,291	)		(520,615	)
Net deferred tax liability	$	(464,574	)	$	(436,748	)

Schedule of reconciliation of beginning and ending amount of unrecognized tax benefits

	2011			2010			2009
Balance at January 1	$	49,396		$	49,587		$	47,875
Increases related to current year tax positions		2,046			300			780
Increases related to prior year tax positions		13,785			1,361			5,099
Decreases related to prior year tax positions		(196	)		(496	)		(3,766	)
Lapses in statutes of limitations		—			(1,128	)		(401	)
Settlements with taxing authorities		(476	)		(228	)		—
Balance at December 31	$	64,555		$	49,396		$	49,587