Stockholders' Equity (Schedule Excercise Of Stock Options) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders' Equity [Abstract]
Intrinsic value of stock options exercised	$ 4,838	$ 1,079	$ 640
Cash receipts upon the exercise of stock options	8,075	997	1,135
Income tax benefits from the exercise of stock options	1,852	422	247
Grant date fair value of stock options that vested	$ 2,814	$ 3,207	$ 2,775