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Debt - Senior Notes and Junior Subordinated Notes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Repayments of long-term debt		$ 350.0	$ 750.0
Junior subordinated notes | On or after March 30, 2029
Debt Instrument [Line Items]
Redemption price percentage		100.00%
Junior subordinated notes | If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage		100.00%
Junior subordinated notes | If a rating agency makes certain changes relating to the equity credit criteria for securities
Debt Instrument [Line Items]
Redemption price percentage		102.00%
2030 Senior Notes | Senior notes
Debt Instrument [Line Items]
Debt interest rate	3.30%	3.30%
Redemption price percentage		100.00%
Applicable basis spread over redemption price percentage		0.40%
2034 Senior Notes | Senior notes
Debt Instrument [Line Items]
Debt interest rate	5.50%	5.50%
Redemption price percentage		100.00%
Applicable basis spread over redemption price percentage		0.25%
2025 Notes | Senior notes
Debt Instrument [Line Items]
Repayments of long-term debt	$ 350.0
Debt interest rate	3.50%	3.50%

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