Loans Held-for-Investment and Allowance for Credit Losses - Schedule of Company's gross charge-offs by origination year and loan class (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	$ 1,841,369
2025	2,254,502	$ 3,092,148
2024	1,098,999	1,422,150
2023	659,270	800,553
2022	1,088,616	1,227,189
2021		672,313
Prior	1,151,729	700,700
Revolving Loans Amortized Cost Basis	252,446	243,223
Total	8,346,931	8,158,276
Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	24
2025	328		$ 10
2024	742		285
2023	545		742
2022	130		775
2021			213
Prior	366		110
Revolving Loans Amortized Cost Basis	0		0
Total	2,135		2,135
C&I [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	349,953
2025	407,006	650,545
2024	115,361	193,758
2023	82,717	105,170
2022	83,741	96,979
2021		33,479
Prior	48,878	36,530
Revolving Loans Amortized Cost Basis	0	0
Total	1,087,656	1,116,461
C&I [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	0
2025	95		0
2024	262		80
2023	11		125
2022	11		142
2021			45
Prior	167		19
Revolving Loans Amortized Cost Basis	0		0
Total	546		411
Municipal [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	134,903
2025	102,914	143,286
2024	27,579	31,910
2023	21,697	22,971
2022	63,778	70,735
2021		9,760
Prior	68,199	63,839
Revolving Loans Amortized Cost Basis	0	0
Total	419,070	342,501
Municipal [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2025			0
2024			0
2023			0
2022			0
2021			0
Prior			0
Revolving Loans Amortized Cost Basis			0
Total			0
Construction & Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	425,828
2025	485,613	774,591
2024	109,497	183,137
2023	73,675	86,985
2022	47,580	55,051
2021		45,210
Prior	47,108	11,568
Revolving Loans Amortized Cost Basis	1,781	1,323
Total	1,191,082	1,157,865
Construction & Development [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	0
2025	0		0
2024	20		40
2023	0		0
2022	9		0
2021			0
Prior	22		0
Revolving Loans Amortized Cost Basis	0		0
Total	51		40
Farm [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	74,051
2025	82,995	92,299
2024	41,519	57,910
2023	24,542	31,917
2022	51,371	59,931
2021		53,598
Prior	70,005	31,970
Revolving Loans Amortized Cost Basis	0	0
Total	344,483	327,625
Farm [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2025			0
2024			0
2023			0
2022			0
2021			0
Prior			0
Revolving Loans Amortized Cost Basis			0
Total			0
Non-Owner Occupied CRE [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	119,509
2025	162,614	183,328
2024	105,343	133,373
2023	38,220	60,214
2022	223,348	239,064
2021		124,904
Prior	182,895	91,933
Revolving Loans Amortized Cost Basis	0	0
Total	831,929	832,816
Non-Owner Occupied CRE [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2025			0
2024			0
2023			250
2022			0
2021			0
Prior			0
Revolving Loans Amortized Cost Basis			0
Total			250
Owner Occupied CRE [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	162,346
2025	222,939	226,943
2024	148,078	175,382
2023	79,878	98,966
2022	242,031	269,976
2021		163,204
Prior	288,821	186,137
Revolving Loans Amortized Cost Basis	0	0
Total	1,144,093	1,120,608
Owner Occupied CRE [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	0
2025	0		0
2024	0		0
2023	0		0
2022	0		175
2021			0
Prior	150		0
Revolving Loans Amortized Cost Basis	0		0
Total	150		175
Residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	271,888
2025	408,417	495,485
2024	366,408	397,363
2023	277,644	307,915
2022	321,218	353,090
2021		221,521
Prior	432,775	275,458
Revolving Loans Amortized Cost Basis	243,650	234,998
Total	2,322,000	2,285,830
Residential [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	0
2025	52		0
2024	197		0
2023	238		240
2022	14		148
2021			5
Prior	3		11
Revolving Loans Amortized Cost Basis	0		0
Total	504		404
Auto [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	222,638
2025	296,422	371,965
2024	160,663	212,681
2023	46,367	66,866
2022	41,914	64,208
2021		14,533
Prior	8,429	2,098
Revolving Loans Amortized Cost Basis	0	0
Total	776,433	732,351
Auto [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	12
2025	64		0
2024	150		122
2023	195		76
2022	79		260
2021			112
Prior	18		46
Revolving Loans Amortized Cost Basis	0		0
Total	518		616
Non-Auto [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	45,175
2025	46,799	70,059
2024	20,791	30,547
2023	12,242	16,557
2022	12,179	15,802
2021		5,508
Prior	4,198	1,068
Revolving Loans Amortized Cost Basis	7,015	6,902
Total	148,399	146,443
Non-Auto [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	12
2025	117		10
2024	73		43
2023	101		51
2022	17		50
2021			51
Prior	0		34
Revolving Loans Amortized Cost Basis	0		0
Total	320		239
Agriculture [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	35,078
2025	38,783	83,647
2024	3,760	6,089
2023	2,288	2,992
2022	1,456	2,353
2021		596
Prior	421	99
Revolving Loans Amortized Cost Basis	0	0
Total	81,786	$ 95,776
Agriculture [Member] \| Total Charge-Offs
Financing Receivable, Allowance for Credit Losses [Line Items]
2026	0
2025	0		0
2024	40		0
2023	0		0
2022	0		0
2021			0
Prior	6		0
Revolving Loans Amortized Cost Basis	0		0
Total	$ 46		$ 0

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