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Debt - Additional Information (Details) - USD ($) |  |  | 3 Months Ended |
--- | --- | --- | --- | ---
Apr. 08, 2019 | Mar. 27, 2019 | Mar. 31, 2019 | Jan. 18, 2019
Senior bank debt | Revolver |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Total available borrowing |  |  |  | $ 1,250,000,000
Additional borrowing amount |  |  |  | 500,000,000
Senior bank debt | Revolver | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on debt variable rate |  |  | 1.10% |
Senior bank debt | Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Total available borrowing |  |  |  | 450,000,000
Additional borrowing amount |  |  |  | $ 75,000,000
Senior bank debt | Term Loan | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on debt variable rate |  |  | 0.875% |
Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2059 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt issued |  | $ 280,000,000.0 |  |
Debt interest rate |  | 5.875% |  |
Debt redemption price percentage of principal amount |  | 100.00% |  |
Debt redemption price percentage of principal amount plus unpaid and accrued interest |  | 102.00% |  |
Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2059 | Subsequent Event |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt issued | $ 300,000,000.0 |  |  |
Additional debt issued | $ 20,000,000 |  |  |
Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2059 | On or after March 30, 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt redemption price percentage of principal amount |  | 100.00% |  |
Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2059 | Prior to March 30, 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt redemption price percentage of principal amount |  | 100.00% |  |

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- Definition Debt Instrument, Redemption Price, Plus Accrued and Unpaid Interest, Percentage + References No definition available. + Details
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- Definition Line of Credit Facility, Maximum Borrowing Capacity, Additional Amount + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph e -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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