Significant Transactions - WM Outrigger Re (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended			12 Months Ended
	Dec. 20, 2022	Jan. 31, 2026	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2025	Dec. 31, 2024
Outrigger Re
Other Significant Transactions [Line Items]
Ceded unearned premiums			$ 230.0	$ 250.0		$ 70.0	$ 230.0
Rollover amount			130.0	$ 130.0
Commitment amount			150.0
Net distributions						9.5	122.7
Short-term investments, at fair value			$ 203.7			$ 245.7	$ 203.7
Outrigger Re | Subsequent Event
Other Significant Transactions [Line Items]
Net distributions		$ 127.7
Outrigger Re
Other Significant Transactions [Line Items]
Business combination, consideration transferred					$ 205.0
Redeemable Preferred Stock | Outrigger Re Ltd
Other Significant Transactions [Line Items]
Issuances of common shares	$ 250.0