INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - Aggregate Principal Payments of Recourse and Non-recourse Debt Payable to Third-parties (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Total Debt Obligations	$ 1,830,595	$ 2,144,418
Unconsolidated Real Estate Ventures
Schedule of Equity Method Investments [Line Items]
2021	148,693
2022	8,543
2023	477,649
2024	328,133
2025	0
Thereafter	0
Real estate property debt	963,018
Net deferred financing costs	(8,224)
Net unamortized premiums/(discounts)	1,894
Total Debt Obligations	$ 956,688

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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