MORTGAGE DEBT - Schedule of Maturities (Details) - Mortgage debt [Member] - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
2020	$ 116.2
2021	167.3
2022	298.0
2023	383.8
2024	201.2
Thereafter	1,484.8
Long-term debt, gross	2,651.3
Unamortized debt premium	4.0
Unamortized loan fees	(14.3)	$ (18.0)
Total Debt	$ 2,641.0	$ 2,950.3

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

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Long-term Debt, Gross, Maturities, Repayments of Principal in Next Twelve Months

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

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Four

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Three

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Two

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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.

+ References

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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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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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