Stockholders' Equity (Schedule Exercise of Stock Options) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders' Equity Note [Abstract]
Intrinsic value of stock options exercised	$ 9,424	$ 7,860	$ 9,062
Cash receipts upon the exercise of stock options	3,280	3,333	13,231
Income tax benefits from the exercise of stock options	2,885	3,660	3,473
Grant date fair value of stock options that vested	$ 1,055	$ 1,561	$ 2,252