Net Income Per Share (EPS) (Schedule Of Weighted Average Number Of Shares) (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Basic shares	46,932	47,425
Contingently issuable shares	113	134
Diluted shares	48,969	49,031
Antidilutive shares	3	177
Employee Stock Options [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Share-based awards	247	100
Restricted Stock Units (RSUs) [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Share-based awards	1,677	1,372
Accounting Standards Update 2016-09 [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Diluted shares	329