FINANCING ARRANGEMENTS - Components of Long-Term Debt (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Principal Amount	$ 1,870.8	$ 1,873.3
Unamortized discount and debt issuance cost	13.1	14.4
Long-term Debt, Total	1,857.7	1,858.9
Less short-term and current portion of long-term debt, Principal Amount	608.6	8.6
Less short-term and current portion of long-term debt, Unamortized discount and debt issuance cost	1.1	0.0
Less short-term and current portion of long-term debt	607.5	8.6
Total long-term debt, gross, net of current	1,262.2	1,864.7
Debt excluding current, unamortized discount and debt issuance costs	12.0	14.4
Total long-term debt, net of current portion	1,250.2	1,850.3
Senior secured revolving credit facility due 2026 \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal Amount	0.0	0.0
Unamortized discount and debt issuance cost	0.0	0.0
Long-term Debt, Total	$ 0.0	$ 0.0
Weighted average interest rate	0.00%	0.00%
Senior secured term loan due 2026 \| Secured Debt
Debt Instrument [Line Items]
Principal Amount	$ 609.8	$ 611.5
Unamortized discount and debt issuance cost	5.7	6.2
Long-term Debt, Total	$ 604.1	$ 605.3
Weighted average interest rate	1.89%	1.85%
5.25% Senior Notes Due 2023 \| Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	5.25%	5.25%
Principal Amount	$ 600.0	$ 600.0
Unamortized discount and debt issuance cost	1.1	1.4
Long-term Debt, Total	$ 598.9	$ 598.6
Weighted average interest rate	5.25%	5.25%
5.75% Senior Notes Due 2025 \| Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	5.75%	5.75%
Principal Amount	$ 650.0	$ 650.0
Unamortized discount and debt issuance cost	6.3	6.8
Long-term Debt, Total	$ 643.7	$ 643.2
Weighted average interest rate	5.75%	5.75%
Other Debt
Debt Instrument [Line Items]
Principal Amount	$ 11.0	$ 11.8
Unamortized discount and debt issuance cost	0.0	0.0
Long-term Debt, Total	$ 11.0	$ 11.8

Debt Instrument, Unamortized Discount (Premium) And Debt Issuance Costs, Current

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Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Noncurrent

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Long-Term Debt, Current Maturities, Principal Amount

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