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Debt and Credit Arrangements Debt Transactions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Instrument [Line Items]
Loss on Extinguishment of Debt	$ 0.0	$ 0.0	$ 0.0	$ (74.0)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	0.4	$ 0.3	0.7	$ (4.9)
4.000% Notes Due 2022
Debt Instrument [Line Items]
Par Value	$ 250.0		$ 250.0
Debt Instrument, Interest Rate, Stated Percentage	4.00%		4.00%
3.750% Notes Due 2023
Debt Instrument [Line Items]
Par Value	$ 500.0		$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	3.75%		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		$ 500.0
Unsecured Debt 4.65% Notes [Member]
Debt Instrument [Line Items]
Par Value	$ 500.0		$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	4.65%		4.65%
Maturity Date			Oct. 01, 2028
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		$ 650.0
Debt Instrument, Interest Rate, Stated Percentage	4.75%		4.75%
Maturity Date			Mar. 30, 2030
Unsecured Debt 2.400% Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.40%		2.40%
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		$ 500.0
Maturity Date			Mar. 01, 2031
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
Unsecured Debt 5.40% Notes [Member]
Debt Instrument [Line Items]
Par Value	$ 500.0		$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	5.40%		5.40%
Maturity Date			Oct. 01, 2048
Unsecured Debt 3.375% Note
Debt Instrument [Line Items]
Par Value	$ 500.0		$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	3.375%		3.375%
Unsecured Debt 4.200% Notes Remaining Principal
Debt Instrument [Line Items]
Par Value	$ 250.0		$ 250.0
Debt Instrument, Interest Rate, Stated Percentage	4.20%		4.20%
Maturity Date			Apr. 15, 2024