Loans Held-for-Investment and Allowance for Credit Losses - Schedule of Loans that are Individually Evaluated for Credit Losses (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	$ 283,104	$ 255,606
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	36,058	28,760
Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	28,371	24,251
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	34,939	30,870
Related Allowance on Collateral Dependent Loans	8,591	8,129
Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	219,794	200,485
Related Allowance on Non-Collateral Dependent Loans	27,467	20,631
Commercial [Member] \| Commercial & Industrial [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	37,228	25,023
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	10,910	8,267
Commercial [Member] \| Commercial & Industrial [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	86	110
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	5,047	3,529
Related Allowance on Collateral Dependent Loans	2,297	1,014
Commercial [Member] \| Commercial & Industrial [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	32,095	21,384
Related Allowance on Non-Collateral Dependent Loans	8,613	7,253
Commercial [Member] \| Municipal [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	8,834	17
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	119	0
Commercial [Member] \| Municipal [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	0	0
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	0	17
Related Allowance on Collateral Dependent Loans	0	0
Commercial [Member] \| Municipal [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	8,834	0
Related Allowance on Non-Collateral Dependent Loans	119	0
Agriculture [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	1,828	2,147
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	172	323
Agriculture [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	0	274
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	1,383	1,348
Related Allowance on Collateral Dependent Loans	75	198
Agriculture [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	445	525
Related Allowance on Non-Collateral Dependent Loans	97	125
Real Estate [Member] \| Construction & Development [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	30,034	20,083
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	2,124	1,961
Real Estate [Member] \| Construction & Development [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	0	0
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	2,651	2,644
Related Allowance on Collateral Dependent Loans	302	171
Real Estate [Member] \| Construction & Development [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	27,383	17,439
Related Allowance on Non-Collateral Dependent Loans	1,822	1,790
Real Estate [Member] \| Farm [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	3,308	7,414
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	0	217
Real Estate [Member] \| Farm [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	1,986	1,858
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	0	208
Related Allowance on Collateral Dependent Loans	0	6
Real Estate [Member] \| Farm [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	1,322	5,348
Related Allowance on Non-Collateral Dependent Loans	0	211
Real Estate [Member] \| Non-Owner Occupied CRE [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	40,056	36,008
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	2,287	3,328
Real Estate [Member] \| Non-Owner Occupied CRE [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	4,595	1,243
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	1,789	1,631
Related Allowance on Collateral Dependent Loans	415	431
Real Estate [Member] \| Non-Owner Occupied CRE [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	33,672	33,134
Related Allowance on Non-Collateral Dependent Loans	1,872	2,897
Real Estate [Member] \| Owner Occupied CRE [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	67,806	62,026
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	7,141	8,727
Real Estate [Member] \| Owner Occupied CRE [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	14,744	15,939
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	8,974	10,667
Related Allowance on Collateral Dependent Loans	3,259	5,348
Real Estate [Member] \| Owner Occupied CRE [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	44,088	35,420
Related Allowance on Non-Collateral Dependent Loans	3,882	3,379
Real Estate [Member] \| Residential [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	90,307	98,492
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	13,296	5,927
Real Estate [Member] \| Residential [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	6,960	4,827
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	14,138	9,731
Related Allowance on Collateral Dependent Loans	2,240	958
Real Estate [Member] \| Residential [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	69,209	83,934
Related Allowance on Non-Collateral Dependent Loans	11,056	4,969
Consumer [Member] \| Auto [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	2,919	3,292
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	6	7
Consumer [Member] \| Auto [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	0	0
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	783	871
Related Allowance on Collateral Dependent Loans	2	2
Consumer [Member] \| Auto [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	2,136	2,421
Related Allowance on Non-Collateral Dependent Loans	4	5
Consumer [Member] \| Non-Auto [Member]
Financing Receivable, Impaired [Line Items]
Total Loans Individually Evaluated for Credit Losses	784	1,104
Total Allowance for Credit Losses on Loans Individually Evaluated for Credit Losses	3	3
Consumer [Member] \| Non-Auto [Member] \| Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Collateral Dependent Loans Individually Evaluated for Credit Losses Without an Allowance	0	0
Collateral Dependent Loans Individually Evaluated for Credit Losses With an Allowance	174	224
Related Allowance on Collateral Dependent Loans	1	1
Consumer [Member] \| Non-Auto [Member] \| Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Non-Collateral Dependent Loans Individually Evaluated for Credit Losses	610	880
Related Allowance on Non-Collateral Dependent Loans	$ 2	$ 2

Loans Held-for-Investment and Allowance for Credit Losses - Schedule of Loans that are Individually Evaluated for Credit Losses (Detail) - USD ($)
$ in Thousands