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Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended				9 Months Ended
	Jul. 29, 2016	Oct. 23, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Jul. 31, 2024	Apr. 30, 2024	Feb. 29, 2024
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, repurchased cost			$ 15.1			$ 40.4	$ 40.4	$ 98.0
Dividends declared			$ 0.28			$ 0.254	$ 0.84	$ 0.762
O 2024 Q1 Dividends [Member]
Equity Class Of Treasury Stock [Line Items]
Quarterly dividends declared					$ 0.28
Dividends payable, date to be paid, year and month											2024-03
O 2024 Q2 Dividends [Member]
Equity Class Of Treasury Stock [Line Items]
Quarterly dividends declared				$ 0.28
Dividends payable, date to be paid, year and month										2024-05
O 2024 Q3 Dividends [Member]
Equity Class Of Treasury Stock [Line Items]
Quarterly dividends declared			$ 0.28
Dividends payable, date to be paid, year and month									2024-08
O 2024 Q4 Dividends [Member] \| Subsequent Event [Member]
Equity Class Of Treasury Stock [Line Items]
Quarterly dividends declared		$ 0.308
Dividends payable, date to be paid, year and month		2024-11
Common Stock
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, expiration date	Dec. 31, 2026
Stock repurchase program, remaining authorized repurchase amount			$ 676.8				$ 676.8
Shares repurchase program, shares repurchased			(125,992)			(534,736)	(352,385)	(1,345,381)
Common Stock \| Share Repurchase Program Excluding Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased			100,000				400,000
Shares repurchase program, repurchased cost				$ 15.0			$ 40.0
Shares repurchase program, average price per share			$ 119.05				$ 113.51
Common Stock \| Share Repurchase Program Including Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased							14,500,000
Shares repurchase program, repurchased cost							$ 1,023.2
Shares repurchase program, average price per share							$ 70.39
Common Stock \| July 2018 Program [Member] \| Maximum [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, authorized amount	$ 150.0
Common Stock \| December 2026 Program [Member] \| Maximum [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, authorized amount	$ 1,700.0