Loans and Allowance for Credit Losses - Schedule of Risk Category of Loans by Class of Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	$ 333,204	$ 212,570
Year 2	192,406	381,734
Year 3	340,844	257,437
Year 4	165,679	180,191
Year 5	149,097	76,935
Prior	173,269	188,808
Revolving Loans Amortized Cost	475,160	461,427
Revolving Loans Converted to Term	855	753
Total	1,830,514	1,759,855
Commercial Real Estate [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	332,078	212,229
Year 2	191,947	379,233
Year 3	337,048	253,837
Year 4	162,180	179,935
Year 5	148,732	75,472
Prior	166,614	186,073
Revolving Loans Amortized Cost	474,324	461,346
Revolving Loans Converted to Term	855	753
Total	1,813,778	1,748,878
Commercial Real Estate [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	331	257
Year 3	103	119
Prior	378	399
Revolving Loans Amortized Cost	497
Total	1,309	775
Commercial Real Estate [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	795	84
Year 2	459	2,501
Year 3	3,693	3,481
Year 4	3,499	256
Year 5	365	1,463
Prior	6,277	2,336
Revolving Loans Amortized Cost	339	81
Total	15,427	10,202
Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	122,798	129,915
Year 2	86,524	111,285
Year 3	69,769	54,661
Year 4	32,519	52,479
Year 5	54,232	30,168
Prior	19,441	10,456
Revolving Loans Amortized Cost	271,921	207,583
Revolving Loans Converted to Term	1,661	1,780
Total	658,865	598,327
Commercial and Industrial [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	114,421	128,598
Year 2	78,335	110,817
Year 3	69,294	54,416
Year 4	32,227	49,557
Year 5	53,119	29,931
Prior	16,902	7,293
Revolving Loans Amortized Cost	261,227	204,237
Revolving Loans Converted to Term	994	1,780
Total	626,519	586,629
Commercial and Industrial [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	121
Year 3	160	15
Year 4	18
Prior	870	992
Revolving Loans Amortized Cost	131
Total	1,300	1,007
Commercial and Industrial [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	8,256	1,317
Year 2	8,189	468
Year 3	315	230
Year 4	274	2,922
Year 5	1,113	237
Prior	1,592	2,171
Revolving Loans Amortized Cost	10,563	3,346
Revolving Loans Converted to Term	667
Total	30,969	10,691
Commercial and Industrial [Member] | Doubtful [Member]
Financing Receivable Recorded Investment [Line Items]
Prior	77
Total	77
Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	25,981	35,040
Year 2	34,128	29,979
Year 3	35,940	277,798
Year 4	260,583	5,205
Year 5	7,745	12,662
Prior	133,912	132,104
Revolving Loans Amortized Cost	67,860	62,409
Revolving Loans Converted to Term	617	1,131
Total	566,766	556,328
Residential Real Estate [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	25,981	35,040
Year 2	33,933	29,766
Year 3	35,687	277,611
Year 4	260,180	5,183
Year 5	7,622	12,506
Prior	130,242	130,144
Revolving Loans Amortized Cost	66,981	57,699
Revolving Loans Converted to Term	572	1,065
Total	561,198	549,014
Residential Real Estate [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Prior	300
Revolving Loans Amortized Cost	72
Revolving Loans Converted to Term	0
Total	372
Residential Real Estate [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 2	195	213
Year 3	253	187
Year 4	403	22
Year 5	123	156
Prior	3,370	1,960
Revolving Loans Amortized Cost	807	4,710
Revolving Loans Converted to Term	45	66
Total	5,196	7,314
Agricultural Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	53,910	23,311
Year 2	18,990	26,920
Year 3	24,758	18,011
Year 4	12,039	18,551
Year 5	20,584	10,754
Prior	40,631	23,626
Revolving Loans Amortized Cost	96,059	74,652
Revolving Loans Converted to Term	277	289
Total	267,248	196,114
Agricultural Real Estate [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	52,369	22,368
Year 2	16,936	26,762
Year 3	24,551	17,987
Year 4	11,468	18,551
Year 5	20,508	10,653
Prior	36,834	20,039
Revolving Loans Amortized Cost	95,410	74,010
Revolving Loans Converted to Term	277	289
Total	258,353	190,659
Agricultural Real Estate [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	1,541	903
Year 2		158
Year 3	151
Prior	138	164
Revolving Loans Amortized Cost	595	605
Total	2,425	1,830
Agricultural Real Estate [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	0	40
Year 2	2,054
Year 3	56	24
Year 4	571
Year 5	76	101
Prior	3,659	3,423
Revolving Loans Amortized Cost	54	37
Total	6,470	3,625
Agricultural [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	15,473	12,463
Year 2	4,230	7,373
Year 3	5,383	5,279
Year 4	2,850	7,777
Year 5	4,078	3,246
Prior	1,376	3,894
Revolving Loans Amortized Cost	53,900	78,500
Revolving Loans Converted to Term	49	55
Total	87,339	118,587
Agricultural [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	15,428	12,424
Year 2	4,045	7,363
Year 3	5,364	4,815
Year 4	2,576	7,148
Year 5	3,674	1,385
Prior	1,308	3,809
Revolving Loans Amortized Cost	53,757	78,285
Revolving Loans Converted to Term	49	55
Total	86,201	115,284
Agricultural [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Prior	32	33
Revolving Loans Amortized Cost	0	9
Total	32	42
Agricultural [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	45	39
Year 2	185	10
Year 3	19	464
Year 4	274	629
Year 5	404	1,861
Prior	36	52
Revolving Loans Amortized Cost	143	206
Total	1,106	3,261
Consumer [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	35,425	47,069
Year 2	17,737	24,861
Year 3	14,446	10,547
Year 4	5,935	4,939
Year 5	2,775	1,330
Prior	2,759	2,908
Revolving Loans Amortized Cost	11,007	12,035
Revolving Loans Converted to Term	0	1
Total	90,084	103,690
Consumer [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	35,412	47,019
Year 2	17,503	24,620
Year 3	14,157	10,384
Year 4	5,765	4,841
Year 5	2,732	1,281
Prior	2,724	2,885
Revolving Loans Amortized Cost	11,007	12,035
Revolving Loans Converted to Term	0	1
Total	89,300	103,066
Consumer [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	13	50
Year 2	234	241
Year 3	289	163
Year 4	170	98
Year 5	43	49
Prior	35	23
Total	784	624
Total Loans Portfolio Segment [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	586,791	460,368
Year 2	354,015	582,152
Year 3	491,140	623,733
Year 4	479,605	269,142
Year 5	238,511	135,095
Prior	371,388	361,796
Revolving Loans Amortized Cost	975,907	896,606
Revolving Loans Converted to Term	3,459	4,009
Total	3,500,816	3,332,901
Total Loans Portfolio Segment [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	575,689	457,678
Year 2	342,699	578,561
Year 3	486,101	619,050
Year 4	474,396	265,215
Year 5	236,387	131,228
Prior	354,624	350,243
Revolving Loans Amortized Cost	962,706	887,612
Revolving Loans Converted to Term	2,747	3,943
Total	3,435,349	3,293,530
Total Loans Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	1,993	1,160
Year 2	0	158
Year 3	414	134
Year 4	18
Prior	1,718	1,588
Revolving Loans Amortized Cost	1,295	614
Total	5,438	3,654
Total Loans Portfolio Segment [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Year 1	9,109	1,530
Year 2	11,316	3,433
Year 3	4,625	4,549
Year 4	5,191	3,927
Year 5	2,124	3,867
Prior	14,969	9,965
Revolving Loans Amortized Cost	11,906	8,380
Revolving Loans Converted to Term	712	66
Total	59,952	$ 35,717
Total Loans Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable Recorded Investment [Line Items]
Prior	77
Total	$ 77