Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Income Tax Disclosure [Abstract]

Schedule Of Income Tax Expense

	Years ended December 31,
(Dollars in thousands)	2014			2013			2012
Current provision (benefit)
Federal	$	15,277		$	(6,137	)	$	3,872
State and local	502			2,145			34
Foreign	3,438			873			2,566
Total current provision (benefit)	19,217			(3,119		)	6,472
Deferred provision (benefit)
Federal	41,087			41,832			45,920
Federal net operating loss	14,522			14,369			11,166
State and local	4,207			5,608			5,270
State tax rate change	(5,374		)	—			—
Foreign	(1		)	(3,478		)	(2,420		)
Total deferred provision	54,441			58,331			59,936
Income tax provision	$	73,658		$	55,212		$	66,408

Schedule of Income before Income Tax, Domestic and Foreign

	Years ended December 31,
(Dollars in thousands)	2014			2013			2012
U.S. sources	$	211,045		$	157,074		$	164,619
Non-U.S. sources	(348		)	(2,709		)	6,335
Income before income tax provision	$	210,697		$	154,365		$	170,954

Schedule Of Income Taxes Calculated On Income Before Income Taxes And Provision For Income Taxes

	Years ended December 31,
	2014		2013		2012
Federal statutory tax rate of 35%	35.0	%	35.0	%	35.0	%
State income tax, net of federal income tax benefit	1.8		4.7		3.1
State tax rate change, net of federal income tax benefit	(2.6	)	—		—
Foreign taxes greater (less) than U.S. statutory rate	1.1		(1.1	)	(1.2	)
Non-deductible operating expenses and tax-exempt income	0.6		0.7		—
Foreign taxes eligible for US foreign tax credit	0.6		0.5		0.5
Fuel tax credit	(1.8	)	(4.5	)	(0.1	)
IRS audit	—		(0.4	)	1.5
Other, net	0.3		0.9		—
Effective income tax rate	35.0	%	35.8	%	38.8	%

Schedule Of Deferred Tax Assets And Liabilities

(Dollars in thousands)	December 31,
	2014			2013
Deferred tax assets
Employee benefits	$	96,420		$	91,474
Self-insurance accruals	26,296			23,042
Domestic operating-loss carryforwards	6,156			22,461
Foreign operating-loss carryforwards	16,723			16,832
Tax-credit carryforwards	10,785			10,019
Share-based compensation	15,171			16,551
Other	11,204			11,471
Valuation allowance	(26,019		)	(25,358		)
Total deferred tax assets	156,736			166,492
Deferred tax liabilities
Property, plant and equipment	351,684			348,728
Prepaid expenses	21,789			24,401
Revenue	6,624			9,013
Other	5,471			6,967
Total deferred tax liabilities	385,568			389,109
Net deferred tax liability	$	(228,832	)	$	(222,617	)

Schedule Of Unrecognized Tax Benefits

(Dollars in thousands)
Balance at December 31, 2012	$	9,728
Gross increases — prior-period tax positions	14
Gross increases — current-period tax positions	1,376
Gross decreases — prior-period tax positions	(602		)
Lapse of statute of limitations	(2,128		)
Balance at December 31, 2013	8,388
Gross increases — current-period tax positions	853
Gross decreases — prior-period tax positions	(900		)
Gross decreases — settlements	(1,744		)
Lapse of statute of limitations	(1,661		)
Balance at December 31, 2014	$	4,936