INVESTMENT SECURITIES - Additional information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
INVESTMENT SECURITIES
HTM securities sold	$ 149,300
Pre tax loss on sale of HTM securities	(11,350)
Available for sale with amortized cost	180,283	$ 136,940
Available for sale, at estimated fair value	154,768	119,436
Held to maturity at amortized cost	0	203,079
Held to maturity, estimated fair value	0	175,392
Asset Pledged as Collateral \| Government public funds held by the bank
INVESTMENT SECURITIES
Available for sale with amortized cost	26,400	2,100
Available for sale, at estimated fair value	22,200	2,000
Held to maturity at amortized cost		12,200
Held to maturity, estimated fair value		10,400
Asset Pledged as Collateral \| FHLB and FRB Borrowing Arrangements
INVESTMENT SECURITIES
Available for sale with amortized cost	49,200
Available for sale, at estimated fair value	$ 41,000
Held to maturity at amortized cost		141,300
Held to maturity, estimated fair value		$ 120,500

Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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