Mortgage Debt - Schedule of Maturities (Details) - Mortgage Debt [Member] - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020 (remainder)	$ 106.7
2021	53.2
2022	293.1
2023	371.1
2024	159.7
Thereafter	1,475.6
Long-term debt, gross	2,459.4
Unamortized debt premium	3.9
Unamortized loan fees	(12.4)	$ (14.3)
Total debt	$ 2,450.9	$ 2,641.0

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

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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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Long-term Debt, Gross, Maturities, Repayments of Principal, Remainder Of Fiscal Year

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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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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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