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Long Term Debt and Lease Obligations, Current and Noncurrent, Including Unamortized Premium (Discount)

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt premium.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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DEBT - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Nov. 19, 2021	Feb. 19, 2020
Debt Instrument [Line Items]
Finance lease liability	$ 8.4	$ 8.4
Total debt outstanding	3,230.1	3,329.2
Less: debt issuance costs	(25.9)	(30.4)
Long-term debt, including current portion	3,206.2	3,301.2
Less—current portion, net of debt issuance costs	(84.9)	(84.5)
Long-term debt	3,121.2	3,216.8
2021 Real Estate Facility \| Bank of America
Debt Instrument [Line Items]
Long-term debt, gross	614.4	660.6
2021 BofA Real Estate Facility \| Wells Fargo
Debt Instrument [Line Items]
Long-term debt, gross	165.9	173.3
2018 BofA Real Estate Facility \| Bank of America
Debt Instrument [Line Items]
Long-term debt, gross	50.3	54.5
2018 Wells Fargo Master Loan Facility \| Wells Fargo
Debt Instrument [Line Items]
Long-term debt, gross	72.0	76.9
2013 BofA Real Estate Facility \| Bank of America
Debt Instrument [Line Items]
Long-term debt, gross	0.0	24.9
2015 Wells Fargo Master Loan Facility \| Wells Fargo
Debt Instrument [Line Items]
Long-term debt, gross	37.2	42.3
2023 Syndicated Revolving Credit Facility \| Bank of America
Debt Instrument [Line Items]
Long-term debt, gross	0.0	0.0
Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 31.9	$ 38.3
Weighted average interest rate	5.90%	5.40%
Senior Notes
Debt Instrument [Line Items]
Add: unamortized premium			$ 3.5
Less: debt issuance costs				$ (17.5)	$ (6.8)
Senior Notes \| 4.50% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term debt, gross	$ 405.0	$ 405.0
Add: unamortized premium	$ 0.6	0.8
Stated interest rate of debt instrument	4.50%		4.50%		4.50%
Senior Notes \| 4.625% Senior Notes due 2029
Debt Instrument [Line Items]
Long-term debt, gross	$ 800.0	800.0
Stated interest rate of debt instrument	4.625%			4.625%
Senior Notes \| 4.75% Senior Notes due 2030
Debt Instrument [Line Items]
Long-term debt, gross	$ 445.0	445.0
Add: unamortized premium	$ 1.3	1.6
Stated interest rate of debt instrument	4.75%		4.75%		4.75%
Senior Notes \| 5.00% Senior Notes due 2032
Debt Instrument [Line Items]
Long-term debt, gross	$ 600.0	$ 600.0
Stated interest rate of debt instrument	5.00%			5.00%