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Earnings Per Share (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Oct. 28, 2020
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount			$ 500,000,000
January 2016 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, shares acquired (in shares)	397,882	1,362,400
Stock repurchase program, average price per share (in dollars per share)	$ 125.67	$ 103.17

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of stock repurchase plan authorized.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
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Number of shares that have been repurchased during the period and are being held in treasury.

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