GOODWILL AND OTHER INTANGIBLE ASSETS - Gross and Net Carrying Amounts of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	$ 26,166	$ 24,766
Accumulated Amortization	17,110	14,414
Net	9,056	10,352
Advisory Contracts
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	23,950	23,950
Accumulated Amortization	16,769	14,376
Net	7,181	9,574
Mortgage Servicing Rights
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	1,243	816
Accumulated Amortization	326	38
Net	917	778
Commercial Servicing Rights
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	973	0
Accumulated Amortization	15	0
Net	$ 958	$ 0