DEBT OBLIGATIONS, NET - Schedule of Maturities (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2018 (Last 9 months)	$ 1,076,682
2019	474,749
2020	552,290
2021	612,634
2022	656,768
Thereafter	1,263,918
Subtotal	4,637,041
Premiums included in mortgage loan financing	6,306
Debt obligations	4,624,608
Senior Unsecured Notes
Long-term Debt, Fiscal Year Maturity [Abstract]
Debt issuance costs	(13,366)
CLO debt
Long-term Debt, Fiscal Year Maturity [Abstract]
Debt issuance costs	$ (5,373)

Debt Obligations

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Amount, after accumulated amortization, of debt premium.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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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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-Publisher FASB
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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 next 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 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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