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LOANS HELD FOR INVESTMENT - Summary of Loans Held for Investment by Category (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	$ 3,053,503		$ 3,055,054
Allowance for credit losses on loans	(44,125)	$ (45,010)	(43,237)	$ (42,886)	$ (43,173)	$ (42,356)
Loans held for investment, net	3,009,378		3,011,817
Commercial Real Estate [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	1,035,926		1,119,063
Allowance for credit losses on loans	(14,937)	(15,706)	(15,973)	(15,924)	(15,593)	(15,808)
Construction [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	97,952		103,855
Allowance for credit losses on loans	(1,901)	(1,948)	(1,943)	(2,078)	(2,040)	(2,391)
Specialized [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	377,783		388,955
Allowance for credit losses on loans	(4,809)	(4,881)	(4,640)	(4,907)	(4,736)	(4,020)
General [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	629,256		557,371
Allowance for credit losses on loans	(7,248)	(7,228)	(6,874)	(6,400)	(6,841)	(6,391)
1-4 Family Residential [Member] \| Consumer [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	592,578		566,400
Allowance for credit losses on loans	(11,080)	(11,150)	(9,677)	(9,558)	(9,702)	(9,177)
Auto Loans [Member] \| Consumer [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	256,281		254,474
Allowance for credit losses on loans	(2,966)	(2,995)	(3,015)	(3,060)	(3,287)	(3,601)
Other Consumer [Member] \| Consumer [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Loans, gross	63,727		64,936
Allowance for credit losses on loans	$ (1,184)	$ (1,102)	$ (1,115)	$ (959)	$ (974)	$ (968)