DEBT OBLIGATIONS AND CREDIT FACILITIES - Future Principal Payments with Respect to the CLO Loans Payable (Details) - Consolidated Funds $ in Thousands	Jun. 30, 2019 USD ($)
Debt Instrument [Line Items]
Remainder of 2019	$ 132,966
2020	0
2021	0
2022	0
2023	0
Thereafter	4,222,587
Total	$ 4,355,553

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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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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