Number of shares that have been repurchased and retired during the period.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Definition

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

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Earnings Per Share (Computation of Basic and Diluted Earnings Per Share) (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		118 Months Ended
	Nov. 06, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Nov. 06, 2020
Subsequent Event [Line Items]
Shares repurchased		965	1,025	2,634	3,585
Average price per share		$ 458.70	$ 377.85	$ 415.28	$ 364.84
Total investment		$ 442,962	$ 387,255	$ 1,093,973	$ 1,307,947
Subsequent event [Member]
Subsequent Event [Line Items]
Shares repurchased	1,000					79,800
Average price per share	$ 454.15					$ 172.09
Total investment	$ 465,300					$ 13,700,000