COMMITMENTS AND CONTINGENCIES (Leases: Assets and Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee, Lease, Description [Line Items]
Lease term	8 years
Operating lease liabilities	$ 168,817
Finance lease obligations	1,651
Accumulated amortization	600
Operating lease expense	28,814	$ 30,497	$ 26,122
Office Space
Lessee, Lease, Description [Line Items]
Operating lease expense	10,500
Ares Management L.P
Lessee, Lease, Description [Line Items]
Operating lease assets	143,406
Finance lease assets	1,787
Total lease assets	145,193
Operating lease liabilities	168,817
Finance lease obligations	1,651
Total lease liabilities	$ 170,468
Minimum
Lessee, Lease, Description [Line Items]
Lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease term	11 years