Earnings Per Share (Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net income	$ 36,086	$ 27,807
Weighted average common shares outstanding	70,274	72,435
Dilutive effect of stock-based awards	298	236
Shares used in computing diluted earnings per share	70,572	72,671
Basic earnings per share	$ 0.51	$ 0.38
Diluted earnings per share	$ 0.51	$ 0.38
Number of antidilutive options that were excluded from computation of earnings per share	0	0