Loans - Risk Category of Loans at Amortized Cost, by Portfolio Segment Based on Year of Origination (Detail) - USD ($)
$ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| Grand Total |
$ 2,737,319
|
$ 2,711,959
|
| Consumer Real Estate [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
59,556
|
52,943
|
| 2025 |
45,543
|
29,131
|
| 2024 |
22,267
|
52,902
|
| 2023 |
44,655
|
71,500
|
| 2022 |
64,621
|
84,077
|
| Prior |
211,427
|
152,521
|
| Term Total |
448,069
|
443,074
|
| Revolving Loans Amortized Cost Basis |
100,912
|
83,338
|
| Revolving Loans Converted to Term |
601
|
631
|
| Grand Total |
549,582
|
527,043
|
| Gross charge-offs - fiscal year 2024 |
41
|
20
|
| Gross charge-offs - Term Total |
41
|
20
|
| Gross charge-offs - Revolving Loans Converted to Term |
3
|
|
| Gross charge-offs - Grand Total |
44
|
20
|
| Consumer Real Estate [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
59,556
|
52,684
|
| 2025 |
45,272
|
28,385
|
| 2024 |
21,542
|
52,324
|
| 2023 |
44,064
|
71,008
|
| 2022 |
64,311
|
82,628
|
| Prior |
209,642
|
150,780
|
| Term Total |
444,387
|
437,809
|
| Revolving Loans Amortized Cost Basis |
100,719
|
83,296
|
| Revolving Loans Converted to Term |
564
|
462
|
| Grand Total |
545,670
|
521,567
|
| Consumer Real Estate [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
0
|
|
| 2025 |
138
|
|
| 2023 |
90
|
|
| 2022 |
202
|
131
|
| Prior |
263
|
47
|
| Term Total |
693
|
178
|
| Revolving Loans Amortized Cost Basis |
19
|
19
|
| Grand Total |
712
|
197
|
| Consumer Real Estate [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
|
259
|
| 2025 |
133
|
746
|
| 2024 |
725
|
578
|
| 2023 |
501
|
492
|
| 2022 |
108
|
1,318
|
| Prior |
1,522
|
1,694
|
| Term Total |
2,989
|
5,087
|
| Revolving Loans Amortized Cost Basis |
174
|
23
|
| Revolving Loans Converted to Term |
37
|
169
|
| Grand Total |
3,200
|
5,279
|
| Agricultural Real Estate [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
28,398
|
28,079
|
| 2025 |
21,399
|
25,648
|
| 2024 |
21,623
|
24,655
|
| 2023 |
20,372
|
31,796
|
| 2022 |
29,340
|
21,307
|
| Prior |
88,926
|
85,257
|
| Term Total |
210,058
|
216,742
|
| Revolving Loans Amortized Cost Basis |
81
|
88
|
| Revolving Loans Converted to Term |
|
0
|
| Grand Total |
210,139
|
216,830
|
| Agricultural Real Estate [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
28,087
|
28,079
|
| 2025 |
21,159
|
20,758
|
| 2024 |
18,613
|
23,792
|
| 2023 |
18,883
|
30,919
|
| 2022 |
26,636
|
20,242
|
| Prior |
88,365
|
84,889
|
| Term Total |
201,743
|
208,679
|
| Revolving Loans Amortized Cost Basis |
81
|
88
|
| Grand Total |
201,824
|
208,767
|
| Agricultural Real Estate [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
311
|
|
| 2025 |
0
|
|
| 2024 |
19
|
|
| 2023 |
1,489
|
32
|
| 2022 |
454
|
|
| Prior |
201
|
282
|
| Term Total |
2,474
|
314
|
| Grand Total |
2,474
|
314
|
| Agricultural Real Estate [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2025 |
240
|
4,890
|
| 2024 |
2,991
|
863
|
| 2023 |
0
|
845
|
| 2022 |
2,250
|
1,065
|
| Prior |
360
|
86
|
| Term Total |
5,841
|
7,749
|
| Grand Total |
5,841
|
7,749
|
| Agricultural [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
37,735
|
42,982
|
| 2025 |
33,346
|
7,208
|
| 2024 |
4,992
|
6,782
|
| 2023 |
4,344
|
8,966
|
| 2022 |
6,775
|
3,168
|
| Prior |
5,246
|
4,373
|
| Term Total |
92,438
|
73,479
|
| Revolving Loans Amortized Cost Basis |
153,535
|
144,447
|
| Revolving Loans Converted to Term |
|
419
|
| Grand Total |
245,973
|
218,345
|
| Agricultural [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
35,167
|
40,636
|
| 2025 |
30,050
|
7,157
|
| 2024 |
4,528
|
6,692
|
| 2023 |
3,931
|
8,617
|
| 2022 |
6,178
|
3,157
|
| Prior |
5,240
|
4,373
|
| Term Total |
85,094
|
70,632
|
| Revolving Loans Amortized Cost Basis |
130,281
|
126,147
|
| Revolving Loans Converted to Term |
|
419
|
| Grand Total |
215,375
|
197,198
|
| Agricultural [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
69
|
53
|
| 2025 |
173
|
22
|
| 2024 |
18
|
|
| 2023 |
49
|
305
|
| 2022 |
277
|
11
|
| Term Total |
586
|
391
|
| Revolving Loans Amortized Cost Basis |
1,150
|
4,417
|
| Grand Total |
1,736
|
4,808
|
| Agricultural [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
2,499
|
2,293
|
| 2025 |
3,123
|
29
|
| 2024 |
446
|
90
|
| 2023 |
364
|
44
|
| 2022 |
320
|
|
| Prior |
6
|
|
| Term Total |
6,758
|
2,456
|
| Revolving Loans Amortized Cost Basis |
22,104
|
13,883
|
| Grand Total |
28,862
|
16,339
|
| Commercial Real Estate [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
205,236
|
250,858
|
| 2025 |
215,783
|
133,526
|
| 2024 |
113,599
|
216,668
|
| 2023 |
172,034
|
388,329
|
| 2022 |
325,896
|
189,307
|
| Prior |
280,355
|
168,962
|
| Term Total |
1,312,903
|
1,347,650
|
| Revolving Loans Amortized Cost Basis |
5,490
|
5,369
|
| Revolving Loans Converted to Term |
|
0
|
| Grand Total |
1,318,393
|
1,353,019
|
| Commercial Real Estate [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
196,958
|
244,689
|
| 2025 |
211,359
|
132,260
|
| 2024 |
104,392
|
157,885
|
| 2023 |
153,024
|
362,675
|
| 2022 |
303,802
|
175,569
|
| Prior |
268,820
|
160,103
|
| Term Total |
1,238,355
|
1,233,181
|
| Revolving Loans Amortized Cost Basis |
5,490
|
5,369
|
| Grand Total |
1,243,845
|
1,238,550
|
| Commercial Real Estate [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
225
|
4,355
|
| 2025 |
2,750
|
1,211
|
| 2024 |
0
|
23,915
|
| 2023 |
15,727
|
12,380
|
| 2022 |
5,749
|
12,381
|
| Prior |
7,590
|
2,088
|
| Term Total |
32,041
|
56,330
|
| Grand Total |
32,041
|
56,330
|
| Commercial Real Estate [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
8,053
|
1,814
|
| 2025 |
1,674
|
55
|
| 2024 |
9,207
|
34,868
|
| 2023 |
3,283
|
13,274
|
| 2022 |
16,345
|
1,357
|
| Prior |
3,945
|
6,771
|
| Term Total |
42,507
|
58,139
|
| Grand Total |
42,507
|
58,139
|
| Commercial & Industrial [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
43,370
|
58,784
|
| 2025 |
51,627
|
20,766
|
| 2024 |
14,652
|
40,685
|
| 2023 |
35,028
|
28,758
|
| 2022 |
22,611
|
10,754
|
| Prior |
8,582
|
6,310
|
| Term Total |
175,870
|
166,057
|
| Revolving Loans Amortized Cost Basis |
167,479
|
147,994
|
| Revolving Loans Converted to Term |
|
45
|
| Grand Total |
343,349
|
314,096
|
| Gross charge-offs - fiscal year 2025 |
|
27
|
| Gross charge-offs - fiscal year 2024 |
|
147
|
| Gross charge-offs - fiscal year 2023 |
|
26
|
| Gross charge-offs - fiscal year 2022 |
39
|
|
| Gross charge-offs - Prior |
|
50
|
| Gross charge-offs - Term Total |
39
|
250
|
| Gross charge-offs - Grand Total |
39
|
250
|
| Commercial & Industrial [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
42,953
|
58,239
|
| 2025 |
51,109
|
20,557
|
| 2024 |
14,613
|
38,008
|
| 2023 |
33,001
|
28,674
|
| 2022 |
22,555
|
10,454
|
| Prior |
8,472
|
6,310
|
| Term Total |
172,703
|
162,242
|
| Revolving Loans Amortized Cost Basis |
156,149
|
135,200
|
| Revolving Loans Converted to Term |
|
45
|
| Grand Total |
328,852
|
297,487
|
| Commercial & Industrial [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
0
|
545
|
| 2025 |
257
|
42
|
| 2024 |
4
|
2,418
|
| 2023 |
2,027
|
63
|
| 2022 |
13
|
165
|
| Term Total |
2,301
|
3,233
|
| Revolving Loans Amortized Cost Basis |
640
|
1,049
|
| Grand Total |
2,941
|
4,282
|
| Commercial & Industrial [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
417
|
|
| 2025 |
261
|
33
|
| 2024 |
35
|
259
|
| 2023 |
|
21
|
| 2022 |
43
|
135
|
| Prior |
110
|
|
| Term Total |
866
|
448
|
| Revolving Loans Amortized Cost Basis |
10,690
|
11,745
|
| Grand Total |
11,556
|
12,193
|
| Commercial & Industrial [Member] | Doubtful [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2025 |
|
134
|
| Term Total |
|
134
|
| Grand Total |
|
134
|
| Consumer [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| Grand Total |
47,794
|
59,493
|
| Consumer [Member] | Payment Performance [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
9,216
|
24,248
|
| 2025 |
17,472
|
8,135
|
| 2024 |
5,344
|
7,872
|
| 2023 |
4,980
|
15,205
|
| 2022 |
8,552
|
2,686
|
| Prior |
1,508
|
820
|
| Term Total |
47,072
|
58,966
|
| Revolving Loans Amortized Cost Basis |
722
|
527
|
| Grand Total |
47,794
|
59,493
|
| Gross charge-offs - fiscal year 2026 |
199
|
339
|
| Gross charge-offs - fiscal year 2025 |
158
|
58
|
| Gross charge-offs - fiscal year 2024 |
44
|
129
|
| Gross charge-offs - fiscal year 2023 |
28
|
169
|
| Gross charge-offs - fiscal year 2022 |
22
|
61
|
| Gross charge-offs - Prior |
8
|
2
|
| Gross charge-offs - Term Total |
459
|
758
|
| Gross charge-offs - Grand Total |
459
|
758
|
| Consumer [Member] | Performing [Member] | Payment Performance [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
9,216
|
24,156
|
| 2025 |
17,472
|
8,134
|
| 2024 |
5,344
|
7,852
|
| 2023 |
4,980
|
15,191
|
| 2022 |
8,535
|
2,671
|
| Prior |
1,500
|
816
|
| Term Total |
47,047
|
58,820
|
| Revolving Loans Amortized Cost Basis |
722
|
527
|
| Grand Total |
47,769
|
59,347
|
| Consumer [Member] | Nonperforming [Member] | Payment Performance [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
|
92
|
| 2025 |
|
1
|
| 2024 |
|
20
|
| 2023 |
|
14
|
| 2022 |
17
|
15
|
| Prior |
8
|
4
|
| Term Total |
25
|
146
|
| Grand Total |
25
|
146
|
| Other Loan [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
326
|
600
|
| 2025 |
571
|
|
| 2022 |
|
14,870
|
| Prior |
21,192
|
7,663
|
| Term Total |
22,089
|
23,133
|
| Grand Total |
22,089
|
23,133
|
| Other Loan [Member] | Pass [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| 2026 |
326
|
600
|
| 2025 |
571
|
|
| 2022 |
|
14,870
|
| Prior |
18,042
|
3,997
|
| Term Total |
18,939
|
19,467
|
| Grand Total |
18,939
|
19,467
|
| Other Loan [Member] | Special Mention [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| Prior |
|
3,666
|
| Term Total |
|
3,666
|
| Grand Total |
|
$ 3,666
|
| Other Loan [Member] | Substandard [Member] |
|
|
| Financing Receivable, Credit Quality Indicator [Line Items] |
|
|
| Prior |
3,150
|
|
| Term Total |
3,150
|
|
| Grand Total |
$ 3,150
|
|