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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%

X

- Definition

Debt Instrument, Redemption Price, Plus Accrued and Unpaid Interest, Percentage

+ References

No definition available.

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- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Additional Amount

+ References

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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.

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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

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

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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- Definition

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

+ References

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-Publisher FASB
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-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
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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

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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