Capital Stock Repurchase Plan Transactions (Schedule Of Repurchased Capital Stock) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Capital Stock Repurchase Plan Transactions [Abstract]
Total cost of repurchased shares	$ 100,235	$ 49,250
Shares repurchased	225,000	150,000
Weighted average price per share	$ 445.49	$ 328.33

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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