Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Income Tax Expense (Benefit) [Abstract]

Components Of Income (Loss) Before Income Taxes

The components of income (loss) before income taxes are as follows:

	Year Ended December 31,
	2012			2011			2010
Domestic	$	586,631		$	404,422		$	339,382
Foreign	(1,462		)	(2,990		)	3,578
	$	585,169		$	401,432		$	342,960

Schedule Of The Provision For (Benefit From) Income Taxes

The Company's provision for (benefit from) income taxes consists of the following:

	Year Ended December 31,
	2012			2011			2010
Current
Federal	$	190,917		$	120,018		$	97,822
State	15,327			8,729			8,128
Foreign	(837		)	(395		)	1,464
	205,407			128,352			107,414
Deferred
Federal	(5,398		)	6,732			7,083
State	(519		)	7,682			6,829
Foreign	124			(300		)	241
	(5,793		)	14,114			14,153
Total provision	$	199,614		$	142,466		$	121,567

Reconciliation Of Taxes Computed At The Statutory Rate To Income Tax Expense

A reconciliation of taxes computed at the statutory rate to the Company's income tax expense is as follows:

	Year Ended December 31,
	2012			2011			2010
Provision for federal income tax at statutory rate	$	204,809		$	140,501		$	120,036
State income tax provision net of federal income tax effect	9,625			10,745			9,372
Foreign tax	(713		)	(695		)	1,705
Foreign losses (earnings)	512			1,047			(1,252		)
Manufacturing deduction	(14,560		)	(9,905		)	(8,750		)
Contingent tax liability	—			(20		)	(411		)
Other, net	(59		)	793			867
	$	199,614		$	142,466		$	121,567

Schedule Of Deferred Tax Assets And Liabilities

The tax effects of the principal temporary differences between financial reporting and income tax reporting at December 31 are as follows:

	2012			2011
Net operating loss carryforward	$	11,922		$	13,958
Credit carryforward	782			769
Accruals	32,486			29,002
Allowance for doubtful accounts	1,540			1,329
Inventories	7,831			7,321
Other	4,704			5,900
Deferred taxes assets—total	59,265			58,279
Property, plant and equipment	(340,237		)	(344,535		)
Turnaround costs	(10,858		)	(11,073		)
Other	(228		)	(914		)
Deferred tax liabilities—total	(351,323		)	(356,522		)
Valuation allowance	(11,927		)	(12,937		)
Total net deferred tax liabilities	$	(303,985	)	$	(311,180	)
Balance sheet classifications
Current deferred tax asset	$	22,305		$	19,611
Noncurrent deferred tax liability	(326,290		)	(330,791		)
Total net deferred tax liabilities	$	(303,985	)	$	(311,180	)

Schedule Of Changes In Gross Unrecognized Tax Benefits

The gross unrecognized tax benefits at December 31 are as follows:

	2012		2011			2010
Beginning balance	$	3,122	$	3,141		$	4,873
Reductions for tax positions for prior years	—		—			(26		)
Reductions due to tax settlements	—		—			(1,389		)
Reductions due to statutes of limitations expiring	—		(19		)	(317		)
Ending balance	$	3,122	$	3,122		$	3,141