CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Unaudited) (USD $) In Thousands, unless otherwise specified	Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Loss	Total
Balance at Dec. 31, 2014	$ 21,654		$ 1,074,561	$ (17,833)	$ 1,078,382
Balance (in shares) at Dec. 31, 2014	216,539
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued for stock incentive plans, net	87	2,357			2,444
Stock issued for stock incentive plans, net (in shares)	869
Stock purchased and retired	(34)	(3,817)	(242)		(4,093)
Stock purchased and retired (in shares)	(339)
Net income			7,548		7,548
Pension adjustment, net of taxes				125	125
Foreign currency translation				(1,029)	(1,029)
Unrealized loss on securities, net of taxes				20	20
Dividends declared			(22,762)		(22,762)
Excess tax benefits for share- based payments		1,460			1,460
Balance at Mar. 31, 2015	$ 21,707		$ 1,059,105	$ (18,717)	$ 1,062,095
Balance (in shares) at Mar. 31, 2015	217,069