Earnings Per Share (Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ 39,044	$ 47,514	$ 118,448	$ 113,585
Weighted average common shares outstanding	69,198	71,436	69,684	72,001
Dilutive effect of stock-based awards	402	316	369	299
Shares used in computing diluted earnings per share	69,600	71,752	70,053	72,300
Basic earnings per share	$ 0.56	$ 0.67	$ 1.70	$ 1.58
Diluted earnings per share	$ 0.56	$ 0.66	$ 1.69	$ 1.57
Number of antidilutive options that were excluded from computation of earnings per share	0	0	0	0