CONSOLIDATED STATEMENT OF STOCKHOLDERS EQUITY (Unaudited) (USD $) In Thousands, except Share data	Total	Common Stock Issued [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2010	$ 240,395	$ 309	$ 135,607	$ (124,464)	$ 228,922	$ 21
Balance (in shares) at Dec. 31, 2010		30,839
Purchase of treasury stock, at cost	(6,639)	0	0	(6,639)	0	0
Exercise of stock options	3,283	0	(966)	4,249	0	0
Income tax benefit from stock-based compensation, net	1,610	0	1,610	0	0	0
Stock-based compensation expense	4,346	0	(140)	4,486	0	0
Other	486	0	82	404	0	0
Dividends paid	(7,953)	0	0	0	(7,953)	0
Change in unrealized gain on marketable securities, net of tax:
Unrealized gain	38	0	0	0	0	38
Net income	15,527	0	0	0	15,527	0
Comprehensive income	15,565	0	0	0	0	0
Balance at Jun. 30, 2011	$ 251,093	$ 309	$ 136,193	$ (121,964)	$ 236,496	$ 59
Balance (in shares) at Jun. 30, 2011		30,839