Earnings per Share Earnings per Share (Schedule of Earnings per Share, Basic and Diluted) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]
Weighted average common shares outstanding, used in computing basic earnings per share	34,378	33,840	33,808
Effect of dilutive stock options and restricted stock units	339	292	396
Weighted-average common shares outstanding, used in computing diluted earnings per share	34,717	34,132	34,204
Basic	$ 2.74	$ 2.95	$ 3.06
Diluted	$ 2.72	$ 2.93	$ 3.03