LOANS HELD FOR INVESTMENT, Age Analysis on Accruing Past-due Loans and Nonaccrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	$ 2,979,063	$ 2,748,081
Nonaccrual	16,561	5,802
Nonaccrual with no ACL	261
Nonaccrual mortgage loans held for sale	0	0
30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	4,795	5,951
90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	4,478	1,987
Commercial Real Estate [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	1,006,909	919,358
Nonaccrual	0	0
Nonaccrual with no ACL	0
Commercial Real Estate [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	65	342
Commercial Real Estate [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	91	27
Commercial [Member] \| Specialized [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	355,252	327,513
Nonaccrual	249	38
Nonaccrual with no ACL	0
Commercial [Member] \| Specialized [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	230	25
Commercial [Member] \| Specialized [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	11	13
Commercial [Member] \| General [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	551,096	484,783
Nonaccrual	14,078	3,357
Nonaccrual with no ACL	0
Commercial [Member] \| General [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	335	1,451
Commercial [Member] \| General [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	3,352	60
Consumer [Member] \| 1-4 Family Residential [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	522,472	460,124
Nonaccrual	1,977	1,356
Nonaccrual with no ACL	261
Consumer [Member] \| 1-4 Family Residential [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	1,829	1,389
Consumer [Member] \| 1-4 Family Residential [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	630	1,653
Consumer [Member] \| Auto Loans [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	318,126	321,476
Nonaccrual	0	0
Nonaccrual with no ACL	0
Consumer [Member] \| Auto Loans [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	971	707
Consumer [Member] \| Auto Loans [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	145	85
Consumer [Member] \| Other Consumer [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	79,795	81,308
Nonaccrual	34	37
Nonaccrual with no ACL	0
Consumer [Member] \| Other Consumer [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	754	1,487
Consumer [Member] \| Other Consumer [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	249	149
Construction [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	145,413	153,519
Nonaccrual	223	1,014
Nonaccrual with no ACL	0
Construction [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	611	550
Construction [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	$ 0	$ 0

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