DEBT OBLIGATIONS - Aggregate Scheduled Principal Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total Debt Obligations	$ 1,830,595	$ 2,144,418
Unsecured Debt
Debt Instrument [Line Items]
2021	0
2022	250,000
2023	350,000
2024	350,000
2025	0
Thereafter	878,610
Total principal payments	1,828,610	1,828,610
Net unamortized premiums/(discounts)	10,137	12,090
Net deferred financing costs	(8,152)	(10,094)
Total Debt Obligations	$ 1,830,595	$ 1,830,606

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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