CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) (USD $) In Thousands, unless otherwise specified	Common Stock [Member]	Capital In Excess of Par Value [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2013	$ 47,872	$ 87,563	$ 228,036	$ 1,786	$ (15,825)	$ 349,432
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	0	0	31,931	0	0	31,931
Other comprehensive income (loss), net of tax	0	0	0	(2,735)	0	(2,735)
Cash dividends paid	0	0	(8,929)	0	0	(8,929)
Purchase of treasury stock	0	0	0	0	(9,487)	(9,487)
Stock-based compensation and related tax benefits	0	1,195	0	0	2,962	4,157
Stock options exercised and related tax benefits	0	17	0	0	122	139
Employee Stock Ownership Plan	0	826	0	0	1,000	1,826
Balance at Sep. 30, 2014	$ 47,872	$ 89,601	$ 251,038	$ (949)	$ (21,228)	$ 366,334