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Long-Term Debt (Schedule of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Jan. 29, 2021	Sep. 13, 2019	Apr. 25, 2017
Debt Instrument [Line Items]
Capitalized lease obligations	$ 128.3
Less unamortized debt issuance costs	(7.7)	$ (9.1)
Total long-term debt	1,801.4	1,806.9
Less current maturities	15.0	15.0
Total long-term debt, net of current	1,786.4	1,791.9
Capitalized lease obligations, autos and equipment, due through 2026
Debt Instrument [Line Items]
Capitalized lease obligations	2.9	2.3
Capitalized lease obligations, buildings, due through 2059
Debt Instrument [Line Items]
Capitalized lease obligations	125.4	131.3
Senior Notes \| 5.625% senior notes due 2027 (net of unamortized discount of $1.3 at September 30, 2023 and $1.6 at December 31, 2022)
Debt Instrument [Line Items]
Long-term debt, gross	$ 298.7	298.4
Stated interest rate	5.625%				5.625%
Unamortized discount	$ 1.3	1.6
Senior Notes \| 4.75% senior notes due 2029 (net of unamortized discount of $3.7 at September 30, 2023 and $4.2 at December 31, 2022)
Debt Instrument [Line Items]
Long-term debt, gross	$ 496.3	495.8
Stated interest rate	4.75%			4.75%
Unamortized discount	$ 3.7	4.2
Senior Notes \| 3.75% senior notes due 2031 (net of unamortized discount of $4.6 at September 30, 2023 and $5.1 at December 31, 2022)
Debt Instrument [Line Items]
Long-term debt, gross	$ 495.4	494.9
Stated interest rate	3.75%		3.75%
Unamortized discount	$ 4.6	5.1
Secured Debt \| Term loan due 2028 (effective interest rate of 7.22% at September 30, 2023 and 5.95% at December 31, 2022 and net of unamortized discount of $0.6 at September 30, 2023 and $0.7 at December 31, 2022) \| Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	390.4	393.3
Unamortized discount	$ 0.6	$ 0.7
Effective interest rate	7.22%	5.95%