Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 3,530	$ 3,746	$ 3,843
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1:	3,746	3,843	3,754
Additions based on tax positions related to current year	600	593	699
Additions based on tax positions of prior years	0	0	119
Reductions for tax positions of prior years	(570)	(579)	(693)
Settlements	(246)	(111)	(36)
Balance at December 31:	3,530	3,746	3,843
Accrued interest and penalties	1,195	1,239
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory federal tax rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal benefit	3.90%	3.60%	2.70%
Other, net	1.60%	(0.10%)	1.40%
Effective tax rate	40.50%	38.50%	39.10%
Income before Income Taxes, Domestic	133,300	121,770	61,338
Income before Income Taxes, Foreign	12,148	11,419	8,136
Income before provision for income taxes	145,448	133,189	69,474
Provisions for Income Taxes Recorded in the Consolidated Statements of Income [Abstract]
US Federal, current expense	38,642	41,052	11,562
State, current expense	6,848	6,343	2,189
Foreign, current expense	3,366	3,579	2,733
Total Current expense	48,856	50,974	16,484
US Federal, deferred expense	9,090	246	9,428
State, deferred expense	786	178	1,198
Foreign, deferred expense	118	(100)	71
Total Deferred expense	9,994	324	10,697
Provision for income taxes	58,850	51,298	27,181
Components of Deferred Tax Assets and Liabilities [Abstract]
Postretirement benefits	32,257	30,731
Payroll accruals	3,095	2,519
Bad debt reserves	2,178	2,662
Other deferred tax assets	10,359	13,916
Pension	55,665	44,464
Inventory	3,174	2,861
Subtotal	106,728	97,153
less: valuation allowances	(285)	(306)
Deferred tax assets	106,443	96,847
Fixed assets	(32,999)	(26,614)
Computer software	(3,708)	(2,778)
Other deferred tax liabilities	(2,184)	(1,477)
Deferred tax liabilities	(38,891)	(30,869)
Net deferred tax assets	67,552	65,978
Deferred tax assets, included in other current assets	3,678	5,931
Deferred tax assets, included in other non-current assets	64,260	60,047
Deferred Tax Liabilities, Net, Current	386	0
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	285	306
Deferred tax assets, state net operting loss carryforwards	1,821	2,251
Deferred tax assets, capital loss carryforwards	0	2,261
Deferred Tax Assets, Valuation Allowance	285	306
Undistributed earnings of non-US subsidiaries	$ 54,440