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Long-term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 2,908.7		$ 2,909.3
Long-term Debt, Fair Value	3,009.1		3,337.4
Long-term Debt, Current Maturities	0.6		0.7
Long-term Debt, Excluding Current Maturities	2,908.1		2,908.6
Loss on Extinguishment of Debt	0.0	$ (74.0)
4.000% Notes Due 2022
Debt Instrument [Line Items]
Par Value	$ 250.0
Interest Rate Stated Percentage	4.00%
3.750% Notes Due 2023
Debt Instrument [Line Items]
Par Value	$ 500.0
Interest Rate Stated Percentage	3.75%
4.200% Notes Due 2024 (less unamortized discount and issuance costs of $0.1 and $0.4, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Effective Interest Rate	4.24%
Long-term Debt, Gross			249.4
4.650% Notes Due 2028 (less unamortized discount and issuance costs of $1.2 and $2.9, 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	$ 1.2
Issuance Cost	2.9
Long-term Debt, Gross	495.9		495.8
4.750% Notes Due 2030 (less unamortized discount and issuance costs of $3.2 and $4.9, 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	$ 3.2
Issuance Cost	4.9
Long-term Debt, Gross	641.9		641.7
2.400% Notes Due 2031 (less unamortized discount and issuance costs of $0.7 and $4.2, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Mar. 01, 2031
Effective Interest Rate	2.512%
Unamortized Discount	$ 0.7
Issuance Cost	4.2
Long-term Debt, Gross	$ 495.1		495.0
3.375% Notes Due 2041 (less unamortized discount and issuance costs of $1.0 and $5.5, respectively)
Debt Instrument [Line Items]
Maturity Date	Mar. 01, 2041
Effective Interest Rate	3.448%
Unamortized Discount	$ 1.0
Issuance Cost	5.5
Long-term Debt, Gross	493.5		493.4
5.400% Notes Due 2048 (less unamortized discount and issuance costs of $2.7 and $4.9, 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	4.9
Long-term Debt, Gross	492.4		492.3
Other notes payable and capitalized leases
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 40.4		$ 41.7
Unsecured Debt 2.400% Note [Member]
Debt Instrument [Line Items]
Interest Rate Stated Percentage	2.40%
Unsecured Debt 3.375% Note
Debt Instrument [Line Items]
Par Value	$ 500.0
Interest Rate Stated Percentage	3.375%
Unsecured Debt 4.200% Notes Remaining Principal
Debt Instrument [Line Items]
Par Value	$ 250.0
Maturity Date	Apr. 15, 2024
Interest Rate Stated Percentage	4.20%
Unamortized Discount	$ 0.1
Issuance Cost	0.4
Long-term Debt, Gross	$ 249.5