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Debt - Senior Notes and Junior Subordinated Notes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 20, 2024
2024 Senior Notes | Senior notes
Debt Instrument [Line Items]
Debt interest rate	4.25%
Redemption price percentage	100.00%
2025 Senior Notes | Senior notes
Debt Instrument [Line Items]
Face amount	$ 350.0
Debt interest rate	3.50%
Redemption price percentage	100.00%
2025 Senior Notes | Senior notes | Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.25%
2030 Senior Notes | Senior notes
Debt Instrument [Line Items]
Face amount	$ 350.0
Debt interest rate	3.30%
Redemption price percentage	100.00%
2030 Senior Notes | Senior notes | Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.40%
2059 Junior Subordinated Notes | Junior subordinated notes
Debt Instrument [Line Items]
Face amount	$ 300.0
Debt interest rate	5.875%
2059 Junior Subordinated Notes | Junior subordinated notes | On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
2059 Junior Subordinated Notes | Junior subordinated notes | If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
2059 Junior Subordinated Notes | 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%
4.750% Junior Subordinated Notes due 2060 | Junior subordinated notes
Debt Instrument [Line Items]
Face amount	$ 275.0
Debt interest rate	4.75%
4.750% Junior Subordinated Notes due 2060 | Junior subordinated notes | On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.750% Junior Subordinated Notes due 2060 | Junior subordinated notes | If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.750% Junior Subordinated Notes due 2060 | 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%
4.200% Junior Subordinated Notes due 2061 | Junior subordinated notes
Debt Instrument [Line Items]
Face amount	$ 200.0
Debt interest rate	4.20%
4.200% Junior Subordinated Notes due 2061 | Junior subordinated notes | On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.200% Junior Subordinated Notes due 2061 | Junior subordinated notes | If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.200% Junior Subordinated Notes due 2061 | 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%
6.750% Junior Subordinated Notes due 2064 | Junior subordinated notes
Debt Instrument [Line Items]
Face amount	$ 450.0	$ 450.0
Debt interest rate	6.75%
6.750% Junior Subordinated Notes due 2064 | Junior subordinated notes | On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
6.750% Junior Subordinated Notes due 2064 | Junior subordinated notes | If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
6.750% Junior Subordinated Notes due 2064 | 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%

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