GOODWILL AND OTHER INTANGIBLE ASSETS--Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Sep. 30, 2024	Mar. 31, 2024	Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 0	$ 1,800	$ 1,788
Other Depreciation and Amortization	3,200		3,100
Amortization of Mortgage Servicing Rights (MSRs)	$ 900		$ 800
Core deposits
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method	accelerated basis
Estimated weighted average life (in years)	3 years
Customer lists
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method	straight-line basis
Customer lists | Summit Funding Group
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 22,000			$ 22,600
Finite-Lived Intangible Assets, Remaining Amortization Period	8 years 9 months 18 days
Customer lists | Bannockburn [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 19,400			20,300
Finite-Lived Intangible Assets, Remaining Amortization Period	5 years 4 months 24 days
Customer lists | Agile Premium Finance
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 2,500			$ 2,500
Finite-Lived Intangible Assets, Remaining Amortization Period	11 years 10 months 24 days