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Shareholders' Equity - Shares Repurchased (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended						6 Months Ended		7 Months Ended	12 Months Ended
	Aug. 03, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Aug. 03, 2022	Dec. 31, 2021
Equity, Class of Treasury Stock [Line Items]
Repurchases of common stock								$ 303.0	$ 165.0
Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased (in shares)		2,605,947	2,738,223	3,725,982	2,918,993	1,887,531	1,986,534				10,519,040
Repurchases of common stock		$ 151.0	$ 155.0	$ 191.0	$ 140.0	$ 88.0	$ 77.0				$ 496.0
Average price paid per share (in dollars per share)		$ 58.03	$ 56.62	$ 51.47	$ 47.76	$ 46.63	$ 38.83				$ 47.19
Settlement of prepaid share repurchases			$ 3.0
Common Shares | Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Repurchase authorized amount	$ 250.0									$ 250.0
Remaining capacity of shares repurchase program	$ 365.0									$ 365.0
Shares repurchased (in shares)	623,528									5,967,698
Repurchases of common stock	$ 35.0									$ 341.0
Average price paid per share (in dollars per share)	$ 55.89									$ 57.16

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The cash outflow to reacquire common stock during the period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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

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