CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]
Balance at Dec. 31, 2011	$ 245,207	$ 309	$ 135,871	$ (134,647)	$ 24	$ 243,650
Balance (in shares) at Dec. 31, 2011		30,839
Purchase of treasury stock, at cost	(3,253)	0	8	(3,261)	0	0
Exercise of stock options	803	0	(446)	1,249	0	0
Income tax benefit from stock-based compensation, net	1,283	0	1,283	0	0	0
Stock-based compensation expense	2,155	0	(48)	2,203	0	0
Other	260	0	2	258	0	0
Dividends paid	(3,899)	0	0	0	0	(3,899)
Unrealized gain on marketable securities, net of tax	35	0	0	0	35	0
Net income	13,884	0	0	0	0	13,884
Balance at Mar. 31, 2012	$ 256,475	$ 309	$ 136,670	$ (134,198)	$ 59	$ 253,635
Balance (in shares) at Mar. 31, 2012		30,839