Capital Stock Repurchase Plan Transactions (Schedule Of Capital Stock Repurchases) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Capital Stock Repurchase Plan Transactions [Abstract]
Total cost of repurchased shares	$ 22,676	$ 3,179	$ 71,926	$ 84,304
Shares repurchased	69,009	10,000	219,009	310,000
Weighted average price per share	$ 328.59	$ 317.86	$ 328.41	$ 271.95

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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