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Earnings Per Share (Narrative) (Details) - USD ($) |  | 6 Months Ended
--- | --- | ---
Jul. 24, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Equity, Class of Treasury Stock [Line Items] |  |  |
Stock repurchase program, authorized amount | $ 400,000,000 |  |
Stock repurchase program, period | 2 years |  |
January 2016 Share Repurchase Program |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Stock repurchase program, shares acquired (in shares) |  | 1,362,400 | 379,754
Stock repurchase program, average price per share (in dollars per share) |  | $ 103.17 | $ 79.32

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- Definition Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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