LOANS HELD FOR INVESTMENT - Age Analysis on Accruing Past-due Loans and Nonaccrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	$ 3,103,529	$ 3,144,502
Total Nonaccrual	3,680	7,070
Nonaccrual with no ACL	1,064	598
Commercial Real Estate [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,052,951	1,064,625
Total Nonaccrual	995	1,402
Nonaccrual with no ACL	54	54
Construction [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	103,444	100,103
Total Nonaccrual	607	0
Nonaccrual with no ACL	607	0
Specialized [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	384,861	409,351
Total Nonaccrual	696	699
Nonaccrual with no ACL	0	544
General [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	654,634	659,323
Total Nonaccrual	533	4,108
Nonaccrual with no ACL	403	0
1-4 Family Residential [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Total Nonaccrual	835	845
Nonaccrual with no ACL	0	0
Auto Loans [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Total Nonaccrual	0	0
Nonaccrual with no ACL	0	0
Other Consumer [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Total Nonaccrual	14	16
Nonaccrual with no ACL	0	0
30-89 Days Past Due [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	7,077	6,514
30-89 Days Past Due [Member] \| Commercial Real Estate [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	834	2,241
30-89 Days Past Due [Member] \| Construction [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	105	455
30-89 Days Past Due [Member] \| Specialized [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,102	264
30-89 Days Past Due [Member] \| General [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,705	1,173
30-89 Days Past Due [Member] \| 1-4 Family Residential [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	2,260	1,221
30-89 Days Past Due [Member] \| Auto Loans [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	379	395
30-89 Days Past Due [Member] \| Other Consumer [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	692	765
90 Days or More Past Due and Still Accruing [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,413	2,735
90 Days or More Past Due and Still Accruing [Member] \| Commercial Real Estate [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	178	206
90 Days or More Past Due and Still Accruing [Member] \| Construction [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	0	578
90 Days or More Past Due and Still Accruing [Member] \| Specialized [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	0	50
90 Days or More Past Due and Still Accruing [Member] \| General [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	41	31
90 Days or More Past Due and Still Accruing [Member] \| 1-4 Family Residential [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	1,061	1,750
90 Days or More Past Due and Still Accruing [Member] \| Auto Loans [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	17	40
90 Days or More Past Due and Still Accruing [Member] \| Other Consumer [Member] \| Commercial [Member]
LOANS HELD FOR INVESTMENT [Abstract]
Past Due	$ 116	$ 80

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

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