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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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