BORROWINGS (Details)	6 Months Ended
	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Borrowings
Borrowing in term FHLB	$ 400,000,000	$ 100,000,000
Carrying Value	173,428,000	173,397,000
Loans held for investment	4,400,000,000	4,300,000,000
Federal Home Loan Bank, maximum borrowing capacity	2,000,000,000.0	2,000,000,000.0
Federal Home Loan Bank, additional credit available	10,000,000	$ 310,000,000
FHLB term advances interest rate		4.21%
Unsecured debt	$ 190,000,000
Number of financial institutions	5
Securities pledged as collateral	$ 83,100,000	$ 76,300,000
FHLB putable advances
Borrowings
FHLB advances	$ 1,000,000,000	$ 800,000,000
Weighted average interest rate	3.74%	3.74%
Minimum
Borrowings
Unsecured debt	$ 20,000,000
Maximum
Borrowings
Unsecured debt	$ 100,000,000
Weighted Average | FHLB putable advances
Borrowings
Weighted average life	6 years 9 months	5 years 4 months 28 days
Revolving Credit Facility
Borrowings
Long-term line of credit	$ 0	$ 0
Debt instrument basis point rate	0.50%
Line of credit, borrowing capacity	$ 20,000,000
FHLB Advances Maturing on May 28, 2027
Borrowings
FHLB advances	$ 300,000,000
Weighted average life	3 years
Interest rate (as a percent)	4.95%
FHLB Advances Maturing on June 28, 2028
Borrowings
FHLB advances	$ 100,000,000
Weighted average life	5 years
Interest rate (as a percent)	4.21%
Overnight FHLB Advance
Borrowings
Secured debt		160,000,000
Repurchase agreements
Borrowings
Secured debt	$ 43,000,000	64,000,000
Federal Reserve Bank advances
Borrowings
Secured debt	273,000,000	285,000,000
Unsecured federal funds
Borrowings
Unsecured debt	0	0
Borrower In Custody
Borrowings
Long-term line of credit		$ 160,000,000
Interest rate (as a percent)		5.50%
Bank Term Funding Program
Borrowings
Long-term line of credit	$ 273,000,000	$ 285,000,000
Debt instrument basis point rate	0.10%
Remaining borrowing capacity	$ 674,000,000	$ 402,000,000