Investments in Unconsolidated Real Estate Ventures - Summary of Debt (Details) - Mortgages Payable - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments
Variable interest rate	2.15%
Variable rate amount	$ 677,246	$ 678,346
Fixed interest rate	4.32%
Fixed rate amount	$ 924,389	925,523
Debt, gross	1,601,635	1,603,869
Unamortized deferred financing costs, net	(9,752)	(10,131)
Long-term debt, net	$ 1,591,883	1,593,738
Investments in Unconsolidated Real Estate Ventures
Schedule of Equity Method Investments
Variable interest rate	2.49%
Variable rate amount	$ 865,653	863,617
Fixed interest rate	4.03%
Fixed rate amount	$ 331,768	323,050
Debt, gross	1,197,421	1,186,667
Unamortized deferred financing costs, net	(6,766)	(7,479)
Long-term debt, net	$ 1,190,655	$ 1,179,188

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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