LOANS HELD FOR INVESTMENT - Age Analysis on Accruing Past-due Loans and Nonaccrual Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	$ 3,144,502	$ 3,055,054
Total Nonaccrual	7,070	22,102
Nonaccrual with no ACL	598	1,575
30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	6,514	7,928
90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	2,735	1,921
Commercial Real Estate [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,064,625	1,119,063
Total Nonaccrual	1,402	19,543
Nonaccrual with no ACL	54	0
Commercial Real Estate [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	2,241	594
Commercial Real Estate [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	206	96
Commercial [Member] \| Specialized [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	409,351	388,955
Total Nonaccrual	699	105
Nonaccrual with no ACL	544	0
Commercial [Member] \| Specialized [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	264	1,770
Commercial [Member] \| Specialized [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	50	240
Commercial [Member] \| General [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	659,323	557,371
Total Nonaccrual	4,108	180
Nonaccrual with no ACL	0	0
Commercial [Member] \| General [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,173	1,374
Commercial [Member] \| General [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	31	244
Consumer [Member] \| 1-4 Family Residential [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	589,851	566,400
Total Nonaccrual	845	676
Nonaccrual with no ACL	0	0
Consumer [Member] \| 1-4 Family Residential [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,221	1,966
Consumer [Member] \| 1-4 Family Residential [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,750	1,042
Consumer [Member] \| Auto Loans [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	259,157	254,474
Total Nonaccrual	0	0
Nonaccrual with no ACL	0	0
Consumer [Member] \| Auto Loans [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	395	1,004
Consumer [Member] \| Auto Loans [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	40	114
Consumer [Member] \| Other Consumer [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	62,092	64,936
Total Nonaccrual	16	23
Nonaccrual with no ACL	0	0
Consumer [Member] \| Other Consumer [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	765	1,125
Consumer [Member] \| Other Consumer [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	80	185
Construction [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	100,103	103,855
Total Nonaccrual	0	1,575
Nonaccrual with no ACL	0	1,575
Construction [Member] \| 30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	455	95
Construction [Member] \| 90 Days or More Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	$ 578	$ 0

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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