MORTGAGE DEBT - Schedule of Maturities (Details) - Mortgage debt - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
2022	$ 17.4
2023	374.8
2024	513.9
2025	482.4
2026	478.2
Thereafter	1,108.4
Long-term debt, gross	2,975.1
Unamortized debt premium	2.5
Unamortized loan fees	(17.8)	$ (12.6)
Total debt	$ 2,959.8	$ 2,589.8

Long-term Debt, Gross, Maturities, Repayments of Principal after Year Five

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