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Debt - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Debt Instrument [Line Items] |  |  |
Debt | $ 2,490,400,000 | $ 2,312,100,000 |
Repayments of long-term debt | 33,000,000.0 | 350,000,000.0 | $ 510,000,000.0
Repurchase of junior convertible securities, equity impact | 7,100,000 |  |
Additional Paid-In Capital |  |  |
Debt Instrument [Line Items] |  |  |
Repurchase of junior convertible securities, equity impact | 7,100,000 |  |
Senior bank debt |  |  |
Debt Instrument [Line Items] |  |  |
Debt | 349,900,000 | 349,800,000 |
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 | 1,500,000 |
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 | 0.95% | 1.02% |
Senior bank debt | Term Loan | LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Basis spread over variable debt rate | 0.85% |  |
Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Debt | $ 1,093,500,000 | $ 1,091,900,000 |
Senior notes | 2024 Senior Notes |  |  |
Debt Instrument [Line Items] |  |  |
Redemption price percentage | 100.00% |  |
Effective interest rate | 4.43% |  |
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% |  |
Effective interest rate | 3.67% |  |
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% |  |
Effective interest rate | 3.39% |  |
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 | $ 751,400,000 | 556,400,000 |
Junior subordinated notes | 2059 Junior Subordinated Notes |  |  |
Debt Instrument [Line Items] |  |  |
Effective interest rate | 5.90% |  |
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] |  |  |
Effective interest rate | 4.78% |  |
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] |  |  |
Effective interest rate | 4.21% |  |
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 | $ 295,600,000 | $ 314,000,000.0 |
Junior convertible securities | Junior Convertible Trust Preferred Securities |  |  |
Debt Instrument [Line Items] |  |  |
Stated interest rate | 5.15% |  |
Deferred tax liability | $ 9,000,000 |  |
Repayments of long-term debt | 33,000,000 |  |
Repurchase of junior convertible securities, debt impact | 29,900,000 |  |
Deferred tax liabilities, net, decrease resulting from repurchase of junior convertible securities | 7,000,000 |  |
Junior convertible securities | Junior Convertible Trust Preferred Securities | Additional Paid-In Capital |  |  |
Debt Instrument [Line Items] |  |  |
Repurchase of junior convertible securities, equity impact | $ 7,100,000 |  |

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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. + References No definition available. + Details
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- Definition Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 25 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=123466103&loc=SL6014347-161799 + Details
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- Definition Net increase or decrease in the carrying amount of the debt instrument for the period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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- Definition Amount of the fee for available but unused credit capacity under the credit facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69C -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69B -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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