Long-term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 3,917.9	$ 3,273.9
Long-term Debt, Fair Value	4,381.3	3,565.5
Long-term Debt, Current Maturities	506.6	502.0
Long-term Debt, Excluding Current Maturities	3,411.3	2,771.9
3.50% Notes Due 2020 (less unamortized discount and issuance costs of $0.0 and $0.0, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2020
Interest Rate Stated Percentage	3.50%
Effective Interest Rate	3.89%
Unamortized Discount	$ 0.0
Issuance Cost	0.0
Long-term Debt, Gross	500.0	498.5
3.75% Notes Due 2021 (less unamortized discount and issuance costs of $0.1 and $1.1, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2021
Interest Rate Stated Percentage	3.75%
Effective Interest Rate	3.98%
Unamortized Discount	$ 0.1
Issuance Cost	1.1
Long-term Debt, Gross	498.8	497.9
4.00% Notes Due 2022 (less unamortized discount and issuance costs of $0.4 and $0.4, respectively)
Debt Instrument [Line Items]
Par Value	$ 250.0
Maturity Date	Mar. 15, 2022
Interest Rate Stated Percentage	4.00%
Effective Interest Rate	4.13%
Unamortized Discount	$ 0.4
Issuance Cost	0.4
Long-term Debt, Gross	249.2	248.7
3.75% Notes Due 2023 (less unamortized discount and issuance costs of $0.4 and $1.0, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Feb. 15, 2023
Interest Rate Stated Percentage	3.75%
Effective Interest Rate	4.32%
Unamortized Discount	$ 0.4
Issuance Cost	1.0
Long-term Debt, Gross	498.6	498.2
4.20% Notes Due 2024 (less unamortized discount and issuance costs of $0.4 and $1.5, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Apr. 15, 2024
Interest Rate Stated Percentage	4.20%
Effective Interest Rate	4.24%
Unamortized Discount	$ 0.4
Issuance Cost	1.5
Long-term Debt, Gross	498.1	497.8
4.65% Notes Due 2028 (less unamortized discount and issuance costs of $1.4 and $3.6, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2028
Interest Rate Stated Percentage	4.65%
Effective Interest Rate	4.78%
Unamortized Discount	$ 1.4
Issuance Cost	3.6
Long-term Debt, Gross	495.0	494.6
4.75% Notes Due 2030 (less unamortized discount and issuance costs of $3.7 and $5.8, respectively)
Debt Instrument [Line Items]
Par Value	$ 650.0
Maturity Date	Mar. 30, 2030
Interest Rate Stated Percentage	4.75%
Effective Interest Rate	4.92%
Unamortized Discount	$ 3.7
Issuance Cost	5.8
Long-term Debt, Gross	640.5	0.0
5.40% Notes Due 2048 (less unamortized discount and issuance costs of $2.7 and $5.2, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2048
Interest Rate Stated Percentage	5.40%
Effective Interest Rate	5.48%
Unamortized Discount	$ 2.7
Issuance Cost	5.2
Long-term Debt, Gross	492.1	491.9
Other notes payable and capitalized leases
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 45.6	$ 46.3

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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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