EQUITY COMPENSATION (Equity Incentive Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Equity compensation
Equity compensation expenses	$ 97,691	$ 89,724	$ 69,711
Restricted units
Equity compensation
Equity compensation expenses	88,979	74,441	54,339
Restricted units with a market condition
Equity compensation
Equity compensation expenses	3,613	1,524	0
Options
Equity compensation
Equity compensation expenses	4,362	12,449	13,848
Phantom Shares
Equity compensation
Equity compensation expenses	$ 737	$ 1,310	$ 1,524
Ares Management L.P
Equity compensation
Total number of shares available for grant under the Equity Incentive Plan (in shares)	28,930,797			32,792,005