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GOODWILL AND OTHER INTANGIBLE ASSETS--Additional Information (Details) - USD ($) $ in Thousands			3 Months Ended			9 Months Ended
	Dec. 31, 2021	Aug. 30, 2019	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Goodwill			$ (1,537)	$ 63,000	$ 0	$ (2,327)	$ 0
Intangible assets amortization			2,783		$ 2,479	$ 8,612	$ 7,438
Core deposits
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method						accelerated basis
Estimated weighted average life (in years)						5 years 6 months
Customer lists
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method						straight-line basis
Estimated weighted average life (in years)	12 years	11 years
Customer lists \| Summit Funding Group
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 30,100		28,300	30,100		$ 28,300
Customer lists \| Bannockburn [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 31,100		$ 28,400	$ 31,100		$ 28,400