Capital Stock Repurchase Plan Transactions (Schedule Of Repurchased Capital Stock) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Capital Stock Repurchase Plan Transactions [Abstract]
Total cost of repurchased shares	$ 24,975	$ 147,123	$ 71,926
Shares repurchased	50,000	325,000	219,009
Weighted average price per share	$ 499.48	$ 452.69	$ 328.41

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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