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Allowance for Credit Losses - Credit risk profile of loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Nonperforming loans past due |  |  | 90 days |  |
Current year | $ 279,816 |  | $ 279,816 |  | $ 410,976
Prior year | 443,248 |  | 443,248 |  | 277,930
Two years before current year | 280,411 |  | 280,411 |  | 468,277
Three years before current year | 435,465 |  | 435,465 |  | 452,136
Four years before current year | 389,774 |  | 389,774 |  | 208,251
Prior | 573,793 |  | 573,793 |  | 486,299
Revolving Loans | 208,307 |  | 208,307 |  | 211,048
Total loans | 2,610,814 |  | 2,610,814 |  | 2,514,917
Current period gross charge offs, Total | 3,226 | $ 6,936 | 9,395 | $ 16,219 |
Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 295,602 |  | 295,602 |  | 359,398
Prior year | 287,298 |  | 287,298 |  | 268,003
Two years before current year | 195,574 |  | 195,574 |  | 252,293
Three years before current year | 187,311 |  | 187,311 |  | 119,148
Four years before current year | 91,783 |  | 91,783 |  | 64,853
Prior | 175,499 |  | 175,499 |  | 152,608
Revolving Loans | 109,995 |  | 109,995 |  | 94,145
Total loans | 1,343,062 |  | 1,343,062 |  | 1,310,448
Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 215 |  | 215 |  | 176
Prior year | 3,487 |  | 3,487 |  | 477
Two years before current year | 776 |  | 776 |  | 1,349
Three years before current year | 935 |  | 935 |  | 771
Four years before current year | 418 |  | 418 |  | 526
Prior | 2,240 |  | 2,240 |  | 2,371
Revolving Loans | 468 |  | 468 |  | 760
Total loans | 8,539 |  | 8,539 |  | 6,430
Total other loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 295,817 |  | 295,817 |  | 359,574
Prior year | 290,785 |  | 290,785 |  | 268,480
Two years before current year | 196,350 |  | 196,350 |  | 253,642
Three years before current year | 188,246 |  | 188,246 |  | 119,919
Four years before current year | 92,201 |  | 92,201 |  | 65,379
Prior | 177,739 |  | 177,739 |  | 154,979
Revolving Loans | 110,463 |  | 110,463 |  | 94,905
Total loans | 1,351,601 |  | 1,351,601 |  | 1,316,878
Residential | First Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 50,005 |  | 50,005 |  | 64,953
Prior year | 66,570 |  | 66,570 |  | 47,930
Two years before current year | 43,592 |  | 43,592 |  | 89,205
Three years before current year | 80,422 |  | 80,422 |  | 69,270
Four years before current year | 63,146 |  | 63,146 |  | 37,771
Prior | 153,852 |  | 153,852 |  | 138,824
Revolving Loans | 1,788 |  | 1,788 |  | 2,279
Total loans | 459,375 |  | 459,375 |  | 450,232
Current period gross charge offs, Prior |  |  | 11 |  | 221
Current period gross charge offs, Total |  |  | 11 |  | 221
Residential | First Liens | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 50,005 |  | 50,005 |  | 64,953
Prior year | 66,465 |  | 66,465 |  | 47,930
Two years before current year | 43,592 |  | 43,592 |  | 89,205
Three years before current year | 80,422 |  | 80,422 |  | 69,090
Four years before current year | 63,100 |  | 63,100 |  | 37,658
Prior | 152,136 |  | 152,136 |  | 136,805
Revolving Loans | 1,788 |  | 1,788 |  | 2,279
Total loans | 457,508 |  | 457,508 |  | 447,920
Residential | First Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year | 105 |  | 105 |  |
Three years before current year |  |  |  |  | 180
Four years before current year | 46 |  | 46 |  | 113
Prior | 1,716 |  | 1,716 |  | 2,019
Total loans | 1,867 |  | 1,867 |  | 2,312
Residential | Home Equity |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 338 |  | 338 |  | 966
Prior year | 933 |  | 933 |  | 562
Two years before current year | 706 |  | 706 |  | 1,058
Three years before current year | 842 |  | 842 |  | 31
Four years before current year | 302 |  | 302 |  | 181
Prior | 1,470 |  | 1,470 |  | 1,257
Revolving Loans | 95,802 |  | 95,802 |  | 85,443
Total loans | 100,393 |  | 100,393 |  | 89,498
Current period gross charge offs, 2022 |  |  |  |  | 22
Current period gross charge offs, 2021 |  |  | 22 |  |
Current period gross charge offs, Prior |  |  | 19 |  | 28
Current period gross charge offs, Revolving Loans |  |  |  |  | 51
Current period gross charge offs, Total |  |  | 41 |  | 101
Residential | Home Equity | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 338 |  | 338 |  | 966
Prior year | 933 |  | 933 |  | 562
Two years before current year | 706 |  | 706 |  | 1,017
Three years before current year | 808 |  | 808 |  | 31
Four years before current year | 260 |  | 260 |  | 143
Prior | 1,288 |  | 1,288 |  | 1,149
Revolving Loans | 95,371 |  | 95,371 |  | 84,723
Total loans | 99,704 |  | 99,704 |  | 88,591
Residential | Home Equity | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Two years before current year |  |  |  |  | 41
Three years before current year | 34 |  | 34 |  |
Four years before current year | 42 |  | 42 |  | 38
Prior | 182 |  | 182 |  | 108
Revolving Loans | 431 |  | 431 |  | 720
Total loans | 689 |  | 689 |  | 907
Residential | Junior Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 16,119 |  | 16,119 |  | 16,989
Prior year | 15,385 |  | 15,385 |  | 12,410
Two years before current year | 10,309 |  | 10,309 |  | 12,631
Three years before current year | 9,885 |  | 9,885 |  | 6,469
Four years before current year | 5,125 |  | 5,125 |  | 5,260
Prior | 11,105 |  | 11,105 |  | 9,375
Revolving Loans | 2,537 |  | 2,537 |  | 1,578
Total loans | 70,465 |  | 70,465 |  | 64,712
Current period gross charge offs, 2023 |  |  |  |  | 15
Current period gross charge offs, Prior |  |  | 73 |  |
Current period gross charge offs, Total |  |  | 73 |  | 15
Residential | Junior Liens | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 16,119 |  | 16,119 |  | 16,989
Prior year | 15,342 |  | 15,342 |  | 12,371
Two years before current year | 10,230 |  | 10,230 |  | 12,590
Three years before current year | 9,865 |  | 9,865 |  | 6,431
Four years before current year | 5,125 |  | 5,125 |  | 5,200
Prior | 11,017 |  | 11,017 |  | 9,229
Revolving Loans | 2,537 |  | 2,537 |  | 1,578
Total loans | 70,235 |  | 70,235 |  | 64,388
Residential | Junior Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year | 43 |  | 43 |  | 39
Two years before current year | 79 |  | 79 |  | 41
Three years before current year | 20 |  | 20 |  | 38
Four years before current year |  |  |  |  | 60
Prior | 88 |  | 88 |  | 146
Total loans | 230 |  | 230 |  | 324
Residential | All Other Residential |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 7,378 |  | 7,378 |  | 17,542
Prior year | 13,247 |  | 13,247 |  | 13,123
Two years before current year | 7,759 |  | 7,759 |  | 6,960
Three years before current year | 4,937 |  | 4,937 |  | 4,472
Four years before current year | 3,695 |  | 3,695 |  | 633
Prior | 1,806 |  | 1,806 |  | 1,595
Revolving Loans | 108 |  | 108 |  | 53
Total loans | 38,930 |  | 38,930 |  | 44,378
Current period gross charge offs, 2021 |  |  |  |  | 6
Current period gross charge offs, Total |  |  |  |  | 6
Residential | All Other Residential | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 7,378 |  | 7,378 |  | 17,542
Prior year | 10,403 |  | 10,403 |  | 13,123
Two years before current year | 7,687 |  | 7,687 |  | 6,960
Three years before current year | 4,937 |  | 4,937 |  | 4,392
Four years before current year | 3,646 |  | 3,646 |  | 628
Prior | 1,797 |  | 1,797 |  | 1,559
Revolving Loans | 108 |  | 108 |  | 53
Total loans | 35,956 |  | 35,956 |  | 44,257
Residential | All Other Residential | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year | 2,844 |  | 2,844 |  |
Two years before current year | 72 |  | 72 |  |
Three years before current year |  |  |  |  | 80
Four years before current year | 49 |  | 49 |  | 5
Prior | 9 |  | 9 |  | 36
Total loans | 2,974 |  | 2,974 |  | 121
Consumer | Motor Vehicle |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 217,580 |  | 217,580 |  | 247,512
Prior year | 187,845 |  | 187,845 |  | 187,480
Two years before current year | 130,514 |  | 130,514 |  | 140,363
Three years before current year | 90,363 |  | 90,363 |  | 37,441
Four years before current year | 18,591 |  | 18,591 |  | 20,416
Prior | 8,405 |  | 8,405 |  | 3,349
Revolving Loans | 10 |  | 10 |  | 11
Total loans | 653,308 |  | 653,308 |  | 636,572
Current period gross charge offs, 2024 |  |  | 250 |  | 478
Current period gross charge offs, 2023 |  |  | 1,543 |  | 2,692
Current period gross charge offs, 2022 |  |  | 1,799 |  | 4,839
Current period gross charge offs, 2021 |  |  | 3,205 |  | 1,751
Current period gross charge offs, 2020 |  |  | 649 |  | 587
Current period gross charge offs, Prior |  |  | 207 |  | 97
Current period gross charge offs, Total |  |  | 7,653 |  | 10,444
Consumer | Motor Vehicle | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 217,368 |  | 217,368 |  | 247,368
Prior year | 187,404 |  | 187,404 |  | 187,134
Two years before current year | 129,967 |  | 129,967 |  | 139,251
Three years before current year | 89,487 |  | 89,487 |  | 37,043
Four years before current year | 18,349 |  | 18,349 |  | 20,130
Prior | 8,181 |  | 8,181 |  | 3,290
Revolving Loans | 10 |  | 10 |  | 11
Total loans | 650,766 |  | 650,766 |  | 634,227
Consumer | Motor Vehicle | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 212 |  | 212 |  | 144
Prior year | 441 |  | 441 |  | 346
Two years before current year | 547 |  | 547 |  | 1,112
Three years before current year | 876 |  | 876 |  | 398
Four years before current year | 242 |  | 242 |  | 286
Prior | 224 |  | 224 |  | 59
Total loans | 2,542 |  | 2,542 |  | 2,345
Consumer | All Other Consumer |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 4,397 |  | 4,397 |  | 11,612
Prior year | 6,805 |  | 6,805 |  | 6,975
Two years before current year | 3,470 |  | 3,470 |  | 3,425
Three years before current year | 1,797 |  | 1,797 |  | 2,236
Four years before current year | 1,342 |  | 1,342 |  | 1,118
Prior | 1,101 |  | 1,101 |  | 579
Revolving Loans | 10,218 |  | 10,218 |  | 5,541
Total loans | 29,130 |  | 29,130 |  | 31,486
Current period gross charge offs, 2024 |  |  | 10 |  | 50
Current period gross charge offs, 2023 |  |  | 177 |  | 197
Current period gross charge offs, 2022 |  |  | 145 |  | 121
Current period gross charge offs, 2021 |  |  | 53 |  | 22
Current period gross charge offs, 2020 |  |  | 38 |  | 16
Current period gross charge offs, Prior |  |  | 4 |  | 24
Current period gross charge offs, Revolving Loans |  |  | 127 |  | 182
Current period gross charge offs, Total |  |  | 554 |  | 612
Consumer | All Other Consumer | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 4,394 |  | 4,394 |  | 11,580
Prior year | 6,751 |  | 6,751 |  | 6,883
Two years before current year | 3,392 |  | 3,392 |  | 3,270
Three years before current year | 1,792 |  | 1,792 |  | 2,161
Four years before current year | 1,303 |  | 1,303 |  | 1,094
Prior | 1,080 |  | 1,080 |  | 576
Revolving Loans | 10,181 |  | 10,181 |  | 5,501
Total loans | 28,893 |  | 28,893 |  | 31,065
Consumer | All Other Consumer | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 3 |  | 3 |  | 32
Prior year | 54 |  | 54 |  | 92
Two years before current year | 78 |  | 78 |  | 155
Three years before current year | 5 |  | 5 |  | 75
Four years before current year | 39 |  | 39 |  | 24
Prior | 21 |  | 21 |  | 3
Revolving Loans | 37 |  | 37 |  | 40
Total loans | $ 237 |  | $ 237 |  | $ 421

X
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