Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of stock repurchase plan authorized.

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

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Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended				12 Months Ended
	Feb. 16, 2022	Jul. 29, 2016	Oct. 31, 2021	Jul. 31, 2021	Apr. 30, 2021	Feb. 28, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2022	Nov. 30, 2021	Aug. 31, 2021	May 31, 2021	Mar. 31, 2021
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, repurchased cost							$ 80.0	$ 44.4	$ 131.3
Quarterly dividends declared				$ 0.21	$ 0.21	$ 0.21
Dividends declared			$ 0.231				$ 0.861	$ 0.810	$ 0.725
Dividends payable, date to be paid, year and month											2021-11	2021-08	2021-05	2021-03
Scenario Forecast [Member]
Equity Class Of Treasury Stock [Line Items]
Dividends declared	$ 0.231
Dividends payable, date to be paid, year and month										2022-03
Common Stock
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, expiration date		Dec. 31, 2023
Stock repurchase program, remaining authorized repurchase amount							$ 513.8
Shares repurchase program, shares repurchased							784,901	508,693	1,525,562
Common Stock \| Share Repurchase Program Excluding Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased							800,000
Shares repurchase program, repurchased cost							$ 80.0
Shares repurchase program, average price per share							$ 101.92
Common Stock \| Share Repurchase Program Including Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased							10,500,000
Shares repurchase program, repurchased cost							$ 686.2
Shares repurchase program, average price per share							$ 65.31
Common Stock \| Maximum [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, authorized amount		$ 1,200.0