Condensed Consolidated Statement of Changes in Stockholders' Equity (USD $) In Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Total
Balance at beginning of period at Dec. 31, 2010	$ 665	$ 355,869	$ (1,480)	$ 61,979	$ (163,216)	$ 253,817
Shares at beginning of period at Dec. 31, 2010	66,542				24,823
Issuance of restricted stock, in shares	1,569
Exercise of stock options and stock appreciation rights, in shares	348
Issuance of restricted stock	16	(16)
Exercise of stock options and stock appreciation rights	4	2,504
Income tax benefit from stock-based compensation		1,190
Employee stock purchase plan		193			133	326
Employee stock purchase plan - shares					(19)
Stock-based compensation expense		5,658				5,658
Pension and postretirement plans, net of tax			28			28
Open market repurchases of common stock - shares					869
Open market repurchases of common stock					(13,304)
Net income				11,625		11,625
Shares repurchased for minimum tax withholding on restricted stock, stock option exercises and stock appreciation rights, in shares					90
Shares repurchased for minimum tax withholding on restricted stock, stock option exercises and stock appreciation rights					(1,585)	1,585
Shares tendered in payment of the exercise price of stock options, in shares					131
Shares tendered in payment of the exercise price of stock options					(2,401)	(2,401)
Balance at end of period at Jun. 30, 2011	$ 685	$ 365,398	$ (1,452)	$ 73,604	$ (180,373)	$ 257,862
Shares at end of period at Jun. 30, 2011	68,459				25,894