Debt - Additional Information (Details)	12 Months Ended
Dec. 31, 2022 USD ($) d $ / shares	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Debt	$ 2,535,300,000	$ 2,490,400,000
Senior bank debt
Debt Instrument [Line Items]
Debt	349,900,000	349,900,000
Senior bank debt \| Revolver
Debt Instrument [Line Items]
Available borrowing	1,250,000,000
Additional borrowing amount	500,000,000
Outstanding borrowings	0	0
Commitment fee amount	1,500,000	1,300,000
Senior bank debt \| Term Loan
Debt Instrument [Line Items]
Available borrowing	350,000,000
Additional borrowing amount	75,000,000
Debt	$ 350,000,000	$ 350,000,000
Weighted average interest rate on amount outstanding	5.27%	0.95%
Senior bank debt \| Term Loan \| SOFR Adjustment
Debt Instrument [Line Items]
Basis spread over variable debt rate	0.10%
Senior bank debt \| Term Loan \| SOFR
Debt Instrument [Line Items]
Basis spread over variable debt rate	0.85%
Senior notes
Debt Instrument [Line Items]
Debt	$ 1,095,200,000	$ 1,093,500,000
Senior notes \| 2024 Senior Notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Stated interest rate	4.25%
Senior notes \| 2024 Senior Notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.25%
Senior notes \| 2025 Senior Notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Stated interest rate	3.50%
Senior notes \| 2025 Senior Notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.25%
Senior notes \| 2030 Senior Notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Stated interest rate	3.30%
Senior notes \| 2030 Senior Notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.40%
Junior subordinated notes
Debt Instrument [Line Items]
Debt	$ 751,600,000	751,400,000
Junior subordinated notes \| 2059 Junior Subordinated Notes
Debt Instrument [Line Items]
Stated interest rate	5.875%
Junior subordinated notes \| 2059 Junior Subordinated Notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 2059 Junior Subordinated Notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 2059 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 \| 2060 Junior Subordinated Notes
Debt Instrument [Line Items]
Stated interest rate	4.75%
Junior subordinated notes \| 2060 Junior Subordinated Notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 2060 Junior Subordinated Notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 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%
Junior subordinated notes \| 2061 Junior Subordinated Notes
Debt Instrument [Line Items]
Stated interest rate	4.20%
Junior subordinated notes \| 2061 Junior Subordinated Notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 2061 Junior Subordinated Notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
Junior subordinated notes \| 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%
Junior convertible securities
Debt Instrument [Line Items]
Debt	$ 338,600,000	295,600,000
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	$ 3,100,000	3,900,000
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	$ 8,000,000
Repayments of convertible debt	60,900,000	33,000,000
Deferred tax liabilities, net, decrease resulting from repurchase of junior convertible securities	$ 11,400,000	$ 7,000,000

Debt Instrument, Convertible, Threshold Percentage

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Debt Instrument, Individual Security, Face Amount

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- Definition

Debt Instrument, Make Whole Premium, Discount Rate, Basis Spread On Variable Rate

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- Definition

Deferred Tax Liabilities, Net, Decrease Resulting From Repurchase Of Debt

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- Definition

Represents the deferred taxes generated from the excess of the interest expense calculated under federal income tax regulations over interest expense as calculated for book purposes.

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- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Additional Amount

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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No definition available.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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