DEBT OBLIGATIONS, NET - Schedule of Maturities (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2019 (last 6 months)	$ 842,102
2020	1,040,826
2021	843,924
2022	655,796
2023	559,305
Thereafter	676,940
Subtotal	4,618,893
Premiums included in mortgage loan financing	5,510
Debt obligations	4,613,088
Senior Unsecured Notes
Long-term Debt, Fiscal Year Maturity [Abstract]
Unamortized debt issuance costs	(9,801)
CLO debt
Long-term Debt, Fiscal Year Maturity [Abstract]
Unamortized debt issuance costs	(971)
Mortgage Loan Financing
Long-term Debt, Fiscal Year Maturity [Abstract]
Unamortized debt issuance costs	$ (543)
Length of extension options	1 year

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- Definition

Debt Obligations

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- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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