Share Repurchase Program (Schedule Of Shares Repurchased) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Proceeds from (Repurchase of) Equity [Abstract]
Shares repurchased	5,698	4,901
Average price per share	$ 264.21	$ 231.81
Total investment	$ 1,505,371	$ 1,136,139