Debt and Financing - Schedule of Debt (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 2,123,800,000
Unaccreted discount and debt issuance costs	(16,800,000)	$ (13,000,000.0)
Hedge accounting fair value adjustment	20,300,000	(3,100,000)
Total	2,127,300,000	1,683,900,000
Notional amount	1,846,200,000	946,900,000
Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 2,123,800,000	1,700,000,000.0
Effective interest rate	4.70%
Senior Notes \| 4.500% fixed-rate notes (2024 Notes)
Debt Instrument [Line Items]
Long-term debt	$ 265,800,000	500,000,000.0
Stated interest rate	4.50%
Effective interest rate	4.70%
Senior Notes \| 4.350% fixed-rate notes ("2025-I Notes")
Debt Instrument [Line Items]
Long-term debt	$ 158,000,000.0	300,000,000.0
Stated interest rate	4.35%
Effective interest rate	4.47%
Senior Notes \| 1.200% fixed-rate notes ("2025-II Notes")
Debt Instrument [Line Items]
Long-term debt	$ 400,000,000.0	0
Stated interest rate	1.20%
Effective interest rate	1.37%
Senior Notes \| 3.750% fixed-rate notes ("2029 Notes")
Debt Instrument [Line Items]
Long-term debt	$ 500,000,000.0	500,000,000.0
Stated interest rate	3.75%
Effective interest rate	3.86%
Senior Notes \| 2.000% fixed-rate notes ("2030 Notes")
Debt Instrument [Line Items]
Long-term debt	$ 400,000,000.0	0
Stated interest rate	2.00%
Effective interest rate	2.12%
Senior Notes \| 5.950% fixed-rate notes ("2041 Notes")
Debt Instrument [Line Items]
Long-term debt	$ 400,000,000.0	400,000,000.0
Stated interest rate	5.95%
Effective interest rate	6.03%
Senior Notes \| 4.500% fixed-rate notes (2024 Notes) - Issued March 2014
Debt Instrument [Line Items]
Stated interest rate	4.50%
Effective interest rate	4.63%
Senior Notes \| 4.500% fixed-rate notes (2024 Notes) - Issued February 2016
Debt Instrument [Line Items]
Effective interest rate	4.87%
Designated derivatives:
Debt Instrument [Line Items]
Notional amount	$ 1,672,100,000	784,000,000.0
Fair value hedges: \| Interest rate swap contracts \| Designated derivatives:
Debt Instrument [Line Items]
Notional amount	$ 300,000,000.0	$ 300,000,000.0

Debt Instrument, Derivative Instruments Fair Value Adjustment

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Amount of unamortized debt discount (premium) and debt issuance costs.

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Nominal or face amount used to calculate payment on derivative.

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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.

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