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COMPENSATION EXPENSE (Stock-Based Compensation Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 22, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant (in shares)	900,000		900,000
Incentive plan shares available for grant (in shares)	300,000		300,000
Stock-based compensation	$ 1,100	$ 2,000	$ 2,946	$ 5,227
Medley Management Inc. 2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)	10,000		10,000
Medley Management Inc. 2014 Omnibus Incentive Plan \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)					19,000
Accumulated Deficit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reclass of cumulative dividends on forfeited RSUs			$ 400	300
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares (in shares)			48,772
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU vesting period			5 years
Fair value of RSUs vested			$ 3,600
Shares vested (in shares)			72,435
Cash used to settle awards	$ 200		$ 200
Reversal of previously recognized compensation			1,200	$ 1,000
Unvested RSU compensation cost not yet recognized	7,400		$ 7,400
Unamortized compensation cost			1 year 8 months 12 days
Restricted Stock Units (RSUs), LLC
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested (in shares)			0
Unvested RSU compensation cost not yet recognized	$ 1,000		$ 1,000