Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	6 Months Ended
	Jul. 01, 2022	Jul. 22, 2022	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
DaVinci Reinsurance Ltd.
Subsequent Event [Line Items]
Parent company ownership in redeemable noncontrolling interest			33.80%	28.70%	28.70%
DaVinci Reinsurance Ltd. \| Subsequent Event
Subsequent Event [Line Items]
Parent company ownership in redeemable noncontrolling interest	30.90%
Common Shares
Subsequent Event [Line Items]
Share repurchase program, shares repurchased (in shares)			874,912
Repurchase of shares			$ 137.5
Share repurchase program, price per share (in dollars per share)			$ 157.19
Common Shares \| Subsequent Event
Subsequent Event [Line Items]
Share repurchase program, shares repurchased (in shares)		175,700
Repurchase of shares		$ 25.3
Share repurchase program, price per share (in dollars per share)		$ 144.07
Third-Party Investors
Subsequent Event [Line Items]
Redemption of shares from redeemable noncontrolling interest			$ 161.6	$ 156.7
Third-Party Investors \| Subsequent Event
Subsequent Event [Line Items]
Redemption of shares from redeemable noncontrolling interest	$ 75.0