Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows From Operating Activities
Net income	$ 79,687	$ 72,602	$ 65,591
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	51,294	47,099	40,351
Deferred compensation	10,252	1,529	5,020
Realized and unrealized (gain) loss on long-term investments	(1,460)	156	(1,367)
Stock-based compensation	3,122	3,676	3,789
Deferred income taxes	134	5,056	5,365
Other non-cash items	2,755	4,967	1,292
Changes in assets and liabilities, excluding effects of acquisitions:
Receivables, net	3,906	(60,842)	(34,449)
Inventories	(50,260)	(12,854)	(16,975)
Other current assets	(2,210)	(2,246)	(576)
Accounts payable and accrued liabilities	24,055	25,901	7,409
Pension liabilities	(4,341)	(2,470)	(2,252)
Environmental and legal liabilities	(66)	(772)	(2,481)
Deferred revenues	(662)	(1,474)	(1,404)
Excess tax benefit from stock options and awards	(7,237)	(2,951)	(3,187)
Net Cash Provided By Operating Activities	108,969	77,377	66,126
Cash Flows From Investing Activities
Expenditures for property, plant and equipment	(83,159)	(83,166)	(73,748)
Asset acquisition (Note 20)			(10,400)
Business acquisitions, net of cash acquired (Note 20)		(13,562)	(9,835)
Sale of mutual funds	537	1,615	780
Other, net	(4,827)	(6,274)	(4,051)
Net Cash Used In Investing Activities	(87,449)	(101,387)	(97,254)
Cash Flows From Financing Activities
Revolving debt and bank overdrafts, net	770	223	16,849
Term Loan		65,000	40,000
Build-to-suit obligation buyout		(12,206)
Other debt borrowings		6,573	6,449
Other debt repayments	(18,460)	(52,454)	(10,427)
Dividends paid	(12,757)	(11,513)	(10,570)
Company stock repurchased	(2,098)	(1,508)	(4,906)
Stock option exercises	4,473	3,228	4,335
Excess tax benefit from stock options and awards	7,237	2,951	3,187
Other, net	(8,640)	(2,398)	(2,544)
Net Cash Provided By (Used In) Financing Activities	(29,475)	(2,104)	42,373
Effect of Exchange Rate Changes on Cash	731	(985)	1,435
Net Increase (Decrease) in Cash and Cash Equivalents	(7,224)	(27,099)	12,680
Cash and Cash Equivalents at Beginning of Year	84,099	111,198	98,518
Cash and Cash Equivalents at End of Year	76,875	84,099	111,198
Supplemental Cash Flow Information
Cash payments of income taxes, net of refunds	29,698	24,327	25,091
Cash payments of interest	$ 10,491	$ 8,647	$ 6,630