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Long-Term Debt (Summary Of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020	Sep. 13, 2019	Apr. 25, 2017
Debt Instrument [Line Items]
Capitalized lease obligations	$ 137.4
Less unamortized debt issuance costs	(12.7)	$ (4.4)
Total long-term debt	1,810.0	1,002.4
Less current maturities	13.2	51.2
Total long-term debt, net of current	1,796.8	951.2
Autos and Equipment
Debt Instrument [Line Items]
Capitalized lease obligations	3.2	2.1
Buildings
Debt Instrument [Line Items]
Capitalized lease obligations	$ 134.2	0.0
Senior Notes | 3.75% Senior Notes Due 2031
Debt Instrument [Line Items]
Stated interest rate	3.75%		3.75%
Unamortized discount	$ 6.1
Long-term debt, gross	$ 493.9	0.0
Senior Notes | 5.625% senior notes due 2027
Debt Instrument [Line Items]
Stated interest rate	5.625%			5.625%
Unamortized discount	$ 2.3	2.4
Long-term debt, gross	297.7	297.6
Senior Notes | 4.75% senior notes due 2029
Debt Instrument [Line Items]
Stated interest rate			4.75%
Senior Notes | 4.75% senior notes due 2029 | Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 494.7	494.6
Secured Debt | 4.75% senior notes due 2029 | Line of Credit
Debt Instrument [Line Items]
Stated interest rate	4.75%
Unamortized discount	$ 5.3	$ 5.4
Secured Debt | Term loan due 2023 | Term facility
Debt Instrument [Line Items]
Effective interest rate		2.67%
Long-term debt, gross	$ 0.0	$ 212.5
Secured Debt | Term loan due 2028 | Term facility
Debt Instrument [Line Items]
Stated interest rate	2.27%
Unamortized discount	$ 1.0
Long-term debt, gross	$ 399.0	$ 0.0

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Amount of short-term and long-term debt and lease obligation.

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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