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v3.25.0.1

Debt - Additional Information (Details) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) d $ / shares | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2024 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Repayments of long-term debt |  | $ 750,000,000.0 | $ 25,000,000.0 | $ 60,800,000 |
Debt |  | 2,620,200,000 | 2,537,500,000 |  |
Senior bank debt |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | 0 | 349,900,000 |  |
Senior bank debt | Term Loan |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Repayments of long-term debt |  | $ 350,000,000.0 |  |  |
Basis spread over variable debt rate |  | 0.10% |  |  |
Outstanding borrowings |  |  | $ 350,000,000.0 |  |
Weighted average interest rate on amount outstanding |  |  | 6.31% |  |
Senior bank debt | Term Loan | Debt Instrument, Adjustment Rate |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread over variable debt rate |  | 0.10% |  |  |
Senior bank debt | Term Loan | Secured Overnight Financing Rate (SOFR) |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread over variable debt rate |  | 0.85% |  |  |
Senior bank debt | Revolver |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Available borrowing |  | $ 1,250,000,000 |  |  |
Additional borrowing amount |  | 500,000,000.0 |  |  |
Outstanding borrowings |  | 0 | $ 0 |  |
Commitment fee amount |  | 1,300,000 | 1,300,000 |  |
Senior notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | $ 1,092,100,000 | 1,096,900,000 |  |
Senior notes | 2024 Senior Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Repayments of long-term debt | $ 400,000,000 |  |  |  |
Stated interest rate | 4.25% |  |  |  |
Senior notes | 2034 Senior Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  | 5.50% |  |  |
Par value |  | $ 400,000,000.0 |  |  | $ 400,000,000.0
Redemption price percentage |  | 100.00% |  |  |
Senior notes | 2025 Senior Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  | 3.50% |  |  |
Par value |  | $ 350,000,000.0 |  |  |
Redemption price percentage |  | 100.00% |  |  |
Applicable basis spread over redemption price percentage |  | 0.25% |  |  |
Senior notes | 2030 Senior Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  | 3.30% |  |  |
Par value |  | $ 350,000,000.0 |  |  |
Redemption price percentage |  | 100.00% |  |  |
Applicable basis spread over redemption price percentage |  | 0.40% |  |  |
Junior subordinated notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | $ 1,189,000,000 | 751,800,000 |  |
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% |  |  |
Junior subordinated notes | 6.750% Junior Subordinated Notes due 2064 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  | 6.75% |  |  |
Par value | $ 450,000,000 | $ 450,000,000.0 |  |  |
Junior subordinated notes | 6.750% Junior Subordinated Notes due 2064 | On or after March 30, 2029 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Redemption price percentage | 100.00% |  |  |  |
Junior convertible securities |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | 339,100,000 | 338,900,000 |  |
Junior convertible securities | Junior Convertible Trust Preferred Securities |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | $ 341,700,000 |  |  |
Stated interest rate |  | 5.15% |  |  |
Unamortized debt issuance expense |  | $ 2,700,000 | $ 2,900,000 |  |
Conversion ratio (in shares) |  | 0.2558 |  |  |
Face amount of convertible security (in dollars per share) | $ / shares |  | $ 50.00 |  |  |
Conversion price (in dollars per share) | $ / shares |  | $ 195.47 |  |  |
Number of trading days closing price has exceeded threshold | d |  | 20 |  |  |
Number of consecutive trading days | d |  | 30 |  |  |
Debt instrument, convertible, threshold percentage |  | 1.30 |  |  |
Deferred tax liability |  | $ 10,000,000 |  |  |

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