Loans Held for Investment and Allowance for Loan Losses - Schedule of Loans that are Individually Evaluated for Credit Losses (Detail) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Financing Receivable, Impaired [Line Items]
Related Allowance	$ 24,892	$ 18,298	$ 17,573
Average Recorded Investment		179,105
Average Recorded Investment	229,923
Average Recorded Investment			176,213
Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		17,279
Recorded Investment With No Allowance	9,696
Recorded Investment With No Allowance			12,626
Recorded Investment With Allowance	53,682	21,533	20,983
Related Allowance	11,946	4,863	3,791
Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	12,946	13,435	13,782
Average Recorded Investment		140,293
Average Recorded Investment	166,545
Average Recorded Investment			142,604
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	5,351	6,676	5,858
Average Recorded Investment		25,218
Average Recorded Investment	25,610		23,498
Commercial [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		310
Recorded Investment With No Allowance	1,137		1,322
Recorded Investment With Allowance	2,815	3,055	2,810
Related Allowance	1,430	2,025	1,363
Commercial [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	3,921	4,651	4,495
Average Recorded Investment		21,853
Average Recorded Investment	21,658		19,366
Commercial [Member] | C&I [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	5,351	6,676	5,858
Average Recorded Investment		23,841
Average Recorded Investment	25,237		22,765
Commercial [Member] | C&I [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		310
Recorded Investment With No Allowance	1,137		1,322
Recorded Investment With Allowance	2,815	3,055	2,810
Related Allowance	1,430	2,025	1,363
Commercial [Member] | C&I [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	3,921	4,651	4,495
Average Recorded Investment		20,476
Average Recorded Investment	21,285		18,633
Commercial [Member] | Municipal [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	0
Average Recorded Investment		1,377
Average Recorded Investment	373		733
Commercial [Member] | Municipal [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		1,377
Average Recorded Investment			733
Agriculture [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	1,728	652	750
Average Recorded Investment		2,116
Average Recorded Investment	3,238		1,459
Agriculture [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		215
Recorded Investment With No Allowance	278		57
Recorded Investment With Allowance	1,810	623	98
Related Allowance	1,092	58	50
Agriculture [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	636	594	700
Average Recorded Investment		1,278
Average Recorded Investment	1,150		1,304
Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	17,643	10,964	10,901
Average Recorded Investment		148,743
Average Recorded Investment	196,694		147,768
Real Estate [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		16,754
Recorded Investment With No Allowance	8,281		11,247
Recorded Investment With Allowance	48,013	17,284	17,494
Related Allowance	9,336	2,779	2,377
Real Estate [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	8,307	8,185	8,524
Average Recorded Investment		114,705
Average Recorded Investment	140,400		119,027
Real Estate [Member] | Construction & Development [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	591	2,026	2,401
Average Recorded Investment		23,207
Average Recorded Investment	10,021		23,989
Real Estate [Member] | Construction & Development [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		2,678
Recorded Investment With No Allowance	1,091		758
Recorded Investment With Allowance	526	617	686
Related Allowance	35	139	148
Real Estate [Member] | Construction & Development [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	556	1,887	2,253
Average Recorded Investment		19,912
Average Recorded Investment	8,404		22,545
Real Estate [Member] | Farm [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	989	1,203	994
Average Recorded Investment		7,759
Average Recorded Investment	10,324		6,166
Real Estate [Member] | Farm [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		553
Recorded Investment With No Allowance	412
Recorded Investment With Allowance	4,326	4,981	4,804
Related Allowance	546	1,070	937
Real Estate [Member] | Farm [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	443	133	57
Average Recorded Investment		2,225
Average Recorded Investment	5,586		1,362
Real Estate [Member] | Non-Owner Occupied CRE [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	3,449	3,554	3,684
Average Recorded Investment		36,534
Average Recorded Investment	38,394		37,139
Real Estate [Member] | Non-Owner Occupied CRE [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		1,991
Recorded Investment With No Allowance	2,234		1,919
Recorded Investment With Allowance	10,553	6,416	6,103
Related Allowance	1,402	889	700
Real Estate [Member] | Non-Owner Occupied CRE [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	2,047	2,665	2,984
Average Recorded Investment		28,127
Average Recorded Investment	25,607		29,117
Real Estate [Member] | Owner Occupied CRE [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	9,597	2,035	1,663
Average Recorded Investment		42,800
Average Recorded Investment	86,775		42,568
Real Estate [Member] | Owner Occupied CRE [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		5,473
Recorded Investment With No Allowance	402		4,661
Recorded Investment With Allowance	29,009	2,339	2,161
Related Allowance	6,709	400	232
Real Estate [Member] | Owner Occupied CRE [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	2,888	1,635	1,431
Average Recorded Investment		34,988
Average Recorded Investment	57,364		35,746
Real Estate [Member] | Residential [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	3,017	2,146	2,159
Average Recorded Investment		38,443
Average Recorded Investment	51,180		37,906
Real Estate [Member] | Residential [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		6,059
Recorded Investment With No Allowance	4,142		3,909
Recorded Investment With Allowance	3,599	2,931	3,740
Related Allowance	644	281	360
Real Estate [Member] | Residential [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	2,373	1,865	1,799
Average Recorded Investment		29,453
Average Recorded Investment	43,439		30,257
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	170	6	64
Average Recorded Investment		3,028
Average Recorded Investment	4,381		3,488
Consumer [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		0
Recorded Investment With No Allowance	0
Recorded Investment With Allowance	1,044	571	581
Related Allowance	88	1	1
Consumer [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	82	5	63
Average Recorded Investment		2,457
Average Recorded Investment	3,337		2,907
Consumer [Member] | Auto [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	5	4	4
Average Recorded Investment		2,323
Average Recorded Investment	3,108		2,589
Consumer [Member] | Auto [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		0
Recorded Investment With No Allowance	0
Recorded Investment With Allowance	546	465	464
Related Allowance	1	1	1
Consumer [Member] | Auto [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	4	3	3
Average Recorded Investment		1,858
Average Recorded Investment	2,562		2,125
Consumer [Member] | Non-Auto [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	165	2	60
Average Recorded Investment		705
Average Recorded Investment	1,273		899
Consumer [Member] | Non-Auto [Member] | Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance	0
Recorded Investment With Allowance	498	106	117
Related Allowance	87
Consumer [Member] | Non-Auto [Member] | Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Related Allowance	78	2	60
Average Recorded Investment		$ 599
Average Recorded Investment	$ 775		$ 782