Debt (Details)	9 Months Ended
Sep. 30, 2018 USD ($) installment
Interest rate swaps
Debt Instrument [Line Items]
Derivative, term of contract	30 days
Interest rate, fair value hedge derivative at fair value, net	$ 22,900,000
Senior Notes
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 800,000,000
Debt instrument, fixed interest rate	5.125%
Debt instrument, issue price, percent	100.00%
Debt instrument, redemption, prince, percentage of principal amount that may be redeemed	40.00%
Senior Notes \| Debt instrument, redemption with the proceeds of certain equity offerings
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	105.125%
Senior Notes \| Debt instrument, redemption excluding make whole premium
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%
Senior Notes \| Debt instrument, redemption due to specific kinds of change of control
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	101.00%
2016 Agreement
Debt Instrument [Line Items]
Debt instrument, interest, additional interest above eurodollar rate	1.00%
2016 Agreement \| Federal Funds Rate
Debt Instrument [Line Items]
Debt instrument, interest, additional interest above federal fund rate	0.50%
Minimum applicable margin rate	0.125%
Maximum applicable margin rate	1.50%
2016 Agreement \| Euro Dollar rate
Debt Instrument [Line Items]
Minimum applicable margin rate	1.125%
Maximum applicable margin rate	2.50%
2016 Agreement \| Term loans \| Bank Term Loan - A Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 1,500,000,000.0
2016 Agreement \| Term loans \| Bank Term Loan - B Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	500,000,000.0
2016 Agreement \| Revolving credit facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 1,200,000,000.0
Bank Term Loan - A Facility \| Term loans
Debt Instrument [Line Items]
Line of credit facility, frequency of payments, number of quarterly installments \| installment	16

Debt instrument interest additional interest above eurodollar rate.

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- Definition

Debt instrument interest additional interest above federal fund rate.

+ References

No definition available.

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- Definition

Debt Instrument, Issue Price, Percent

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No definition available.

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- Definition

Debt Instrument, Redemption Price, Percentage of Principal Amount That May Be Redeemed

+ References

No definition available.

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Line of Credit Facility, Frequency of Payments, Number of Quarterly Installments

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Maximum applicable margin rate.

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Minimum applicable margin rate.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of all derivatives designated as interest rate fair value hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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

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

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