Capital Stock Repurchase Plan Transactions (Schedule Of Capital Stock Repurchases) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Capital Stock Repurchases Plan Transactions [Abstract]
Total cost of repurchased shares	$ 18,230	$ 40,610	$ 47,992	$ 99,103
Shares repurchased	135,765	400,000	385,765	1,082,934
Weighted average price per share	$ 134.28	$ 101.53	$ 124.41	$ 91.51