Debt and Credit Arrangements Debt Transactions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Debt Instrument [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$ 0.4	$ 0.3
Unsecured Debt 4.65% Notes [Member]
Debt Instrument [Line Items]
Par Value	$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	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
Debt Instrument, Interest Rate, Stated Percentage	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%
2.400% 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
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
Debt Instrument, Interest Rate, Stated Percentage	5.40%
Maturity Date	Oct. 01, 2048
Unsecured Debt 3.375% Note
Debt Instrument [Line Items]
Par Value	$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	3.375%
Unsecured Debt 4.200% Notes Remaining Principal
Debt Instrument [Line Items]
Par Value	$ 250.0
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Maturity Date	Apr. 15, 2024

Face (par) amount of debt instrument at time of issuance.

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

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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