Debt and Credit Facilities (Summary of Debt) (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Total borrowings outstanding	$ 2,079.1	$ 2,012.5
Discounts and debt issuance costs, net	(11.9)	(13.0)
Total debt	2,067.2	1,999.5
Less current portion of long-term debt	24.9	21.9
Total long-term debt	2,042.3	1,977.6
Line of Credit \| Term Loan
Debt Instrument [Line Items]
Total borrowings outstanding	203.1	212.5
Line of Credit \| Revolving Facility
Debt Instrument [Line Items]
Total borrowings outstanding	$ 76.0	0.0
Senior Notes \| 3.550% Senior Note due 2027
Debt Instrument [Line Items]
Stated interest rate	3.55%
Total borrowings outstanding	$ 400.0	400.0
Senior Notes \| 3.500% Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate	3.50%
Total borrowings outstanding	$ 400.0	400.0
Senior Notes \| 5.411% Senior Notes Due 2032
Debt Instrument [Line Items]
Total borrowings outstanding	600.0	600.0
Senior Notes \| Five Point Six Percent Senior Notes Due 2034
Debt Instrument [Line Items]
Total borrowings outstanding	$ 400.0	$ 400.0

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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