Mortgage and Other Indebtedness, Net- Scheduled Principal Payments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020	$ 18,988
2021	559,094
2022	408,235
2023	1,493,534
2024	343,601
2025	38,472
Thereafter	764,380
Long-term Debt, Gross	3,626,304
Net unamortized discounts and premium	(8,634)
Unamortized deferred financing costs	(13,864)	$ (16,148)
Mortgage and other indebtedness, net	$ 3,729,686	$ 3,527,015
Weighted-average remaining term to maturity	3 years 1 month 6 days	3 years 8 months 12 days
Operating Property Loan \| Mortgages
Debt Instrument [Line Items]
Mortgage and other indebtedness, net	$ 125,880

Debt instrument weighted average remaining term to maturity.

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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 discount (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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