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Allowance for Credit Losses - Credit risk profile of loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Nonperforming loans past due |  |  | 90 days |  |
Current year | $ 168,676 |  | $ 168,676 |  | $ 410,976
Prior year | 440,511 |  | 440,511 |  | 277,930
Two years before current year | 287,223 |  | 287,223 |  | 468,277
Three years before current year | 449,370 |  | 449,370 |  | 452,136
Four years before current year | 418,067 |  | 418,067 |  | 208,251
Prior | 611,495 |  | 611,495 |  | 486,299
Revolving Loans | 172,013 |  | 172,013 |  | 211,048
Total loans | 2,547,355 |  | 2,547,355 |  | 2,514,917
Current period gross charge offs, Total | 2,928 | $ 6,091 | 6,169 | $ 9,283 |
Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 202,615 |  | 202,615 |  | 359,398
Prior year | 316,235 |  | 316,235 |  | 268,003
Two years before current year | 218,247 |  | 218,247 |  | 252,293
Three years before current year | 208,463 |  | 208,463 |  | 119,148
Four years before current year | 99,985 |  | 99,985 |  | 64,853
Prior | 189,495 |  | 189,495 |  | 152,608
Revolving Loans | 103,329 |  | 103,329 |  | 94,145
Total loans | 1,338,369 |  | 1,338,369 |  | 1,310,448
Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 51 |  | 51 |  | 176
Prior year | 466 |  | 466 |  | 477
Two years before current year | 709 |  | 709 |  | 1,349
Three years before current year | 1,091 |  | 1,091 |  | 771
Four years before current year | 546 |  | 546 |  | 526
Prior | 2,322 |  | 2,322 |  | 2,371
Revolving Loans | 382 |  | 382 |  | 760
Total loans | 5,567 |  | 5,567 |  | 6,430
Total other loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 202,666 |  | 202,666 |  | 359,574
Prior year | 316,701 |  | 316,701 |  | 268,480
Two years before current year | 218,956 |  | 218,956 |  | 253,642
Three years before current year | 209,554 |  | 209,554 |  | 119,919
Four years before current year | 100,531 |  | 100,531 |  | 65,379
Prior | 191,817 |  | 191,817 |  | 154,979
Revolving Loans | 103,711 |  | 103,711 |  | 94,905
Total loans | 1,343,936 |  | 1,343,936 |  | 1,316,878
Residential | First Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 32,942 |  | 32,942 |  | 64,953
Prior year | 65,681 |  | 65,681 |  | 47,930
Two years before current year | 45,769 |  | 45,769 |  | 89,205
Three years before current year | 84,703 |  | 84,703 |  | 69,270
Four years before current year | 65,013 |  | 65,013 |  | 37,771
Prior | 162,173 |  | 162,173 |  | 138,824
Revolving Loans | 1,454 |  | 1,454 |  | 2,279
Total loans | 457,735 |  | 457,735 |  | 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 | 32,942 |  | 32,942 |  | 64,953
Prior year | 65,681 |  | 65,681 |  | 47,930
Two years before current year | 45,769 |  | 45,769 |  | 89,205
Three years before current year | 84,703 |  | 84,703 |  | 69,090
Four years before current year | 64,884 |  | 64,884 |  | 37,658
Prior | 160,337 |  | 160,337 |  | 136,805
Revolving Loans | 1,454 |  | 1,454 |  | 2,279
Total loans | 455,770 |  | 455,770 |  | 447,920
Residential | First Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Three years before current year |  |  |  |  | 180
Four years before current year | 129 |  | 129 |  | 113
Prior | 1,836 |  | 1,836 |  | 2,019
Total loans | 1,965 |  | 1,965 |  | 2,312
Residential | Home Equity |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 421 |  | 421 |  | 966
Prior year | 914 |  | 914 |  | 562
Two years before current year | 273 |  | 273 |  | 1,058
Three years before current year | 813 |  | 813 |  | 31
Four years before current year | 170 |  | 170 |  | 181
Prior | 1,721 |  | 1,721 |  | 1,257
Revolving Loans | 91,127 |  | 91,127 |  | 85,443
Total loans | 95,439 |  | 95,439 |  | 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 | 421 |  | 421 |  | 966
Prior year | 914 |  | 914 |  | 562
Two years before current year | 273 |  | 273 |  | 1,017
Three years before current year | 777 |  | 777 |  | 31
Four years before current year | 146 |  | 146 |  | 143
Prior | 1,610 |  | 1,610 |  | 1,149
Revolving Loans | 90,768 |  | 90,768 |  | 84,723
Total loans | 94,909 |  | 94,909 |  | 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 | 36 |  | 36 |  |
Four years before current year | 24 |  | 24 |  | 38
Prior | 111 |  | 111 |  | 108
Revolving Loans | 359 |  | 359 |  | 720
Total loans | 530 |  | 530 |  | 907
Residential | Junior Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 8,157 |  | 8,157 |  | 16,989
Prior year | 16,381 |  | 16,381 |  | 12,410
Two years before current year | 11,139 |  | 11,139 |  | 12,631
Three years before current year | 10,700 |  | 10,700 |  | 6,469
Four years before current year | 5,529 |  | 5,529 |  | 5,260
Prior | 12,342 |  | 12,342 |  | 9,375
Revolving Loans | 2,777 |  | 2,777 |  | 1,578
Total loans | 67,025 |  | 67,025 |  | 64,712
Current period gross charge offs, 2023 |  |  |  |  | 15
Current period gross charge offs, Prior |  |  | 65 |  |
Current period gross charge offs, Total |  |  | 65 |  | 15
Residential | Junior Liens | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 8,157 |  | 8,157 |  | 16,989
Prior year | 16,381 |  | 16,381 |  | 12,371
Two years before current year | 11,097 |  | 11,097 |  | 12,590
Three years before current year | 10,680 |  | 10,680 |  | 6,431
Four years before current year | 5,529 |  | 5,529 |  | 5,200
Prior | 12,253 |  | 12,253 |  | 9,229
Revolving Loans | 2,777 |  | 2,777 |  | 1,578
Total loans | 66,874 |  | 66,874 |  | 64,388
Residential | Junior Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year |  |  |  |  | 39
Two years before current year | 42 |  | 42 |  | 41
Three years before current year | 20 |  | 20 |  | 38
Four years before current year |  |  |  |  | 60
Prior | 89 |  | 89 |  | 146
Total loans | 151 |  | 151 |  | 324
Residential | All Other Residential |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 5,537 |  | 5,537 |  | 17,542
Prior year | 16,649 |  | 16,649 |  | 13,123
Two years before current year | 8,592 |  | 8,592 |  | 6,960
Three years before current year | 4,992 |  | 4,992 |  | 4,472
Four years before current year | 3,918 |  | 3,918 |  | 633
Prior | 2,133 |  | 2,133 |  | 1,595
Revolving Loans | 378 |  | 378 |  | 53
Total loans | 42,199 |  | 42,199 |  | 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 | 5,537 |  | 5,537 |  | 17,542
Prior year | 16,649 |  | 16,649 |  | 13,123
Two years before current year | 8,592 |  | 8,592 |  | 6,960
Three years before current year | 4,992 |  | 4,992 |  | 4,392
Four years before current year | 3,867 |  | 3,867 |  | 628
Prior | 2,123 |  | 2,123 |  | 1,559
Revolving Loans | 378 |  | 378 |  | 53
Total loans | 42,138 |  | 42,138 |  | 44,257
Residential | All Other Residential | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Three years before current year |  |  |  |  | 80
Four years before current year | 51 |  | 51 |  | 5
Prior | 10 |  | 10 |  | 36
Total loans | 61 |  | 61 |  | 121
Consumer | Motor Vehicle |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 152,061 |  | 152,061 |  | 247,512
Prior year | 208,697 |  | 208,697 |  | 187,480
Two years before current year | 148,783 |  | 148,783 |  | 140,363
Three years before current year | 106,123 |  | 106,123 |  | 37,441
Four years before current year | 24,284 |  | 24,284 |  | 20,416
Prior | 12,180 |  | 12,180 |  | 3,349
Revolving Loans | 10 |  | 10 |  | 11
Total loans | 652,138 |  | 652,138 |  | 636,572
Current period gross charge offs, 2024 |  |  | 32 |  | 478
Current period gross charge offs, 2023 |  |  | 966 |  | 2,692
Current period gross charge offs, 2022 |  |  | 1,107 |  | 4,839
Current period gross charge offs, 2021 |  |  | 2,274 |  | 1,751
Current period gross charge offs, 2020 |  |  | 437 |  | 587
Current period gross charge offs, Prior |  |  | 191 |  | 97
Current period gross charge offs, Total |  |  | 5,007 |  | 10,444
Consumer | Motor Vehicle | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 152,010 |  | 152,010 |  | 247,368
Prior year | 208,316 |  | 208,316 |  | 187,134
Two years before current year | 148,240 |  | 148,240 |  | 139,251
Three years before current year | 105,094 |  | 105,094 |  | 37,043
Four years before current year | 24,013 |  | 24,013 |  | 20,130
Prior | 11,927 |  | 11,927 |  | 3,290
Revolving Loans | 10 |  | 10 |  | 11
Total loans | 649,610 |  | 649,610 |  | 634,227
Consumer | Motor Vehicle | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 51 |  | 51 |  | 144
Prior year | 381 |  | 381 |  | 346
Two years before current year | 543 |  | 543 |  | 1,112
Three years before current year | 1,029 |  | 1,029 |  | 398
Four years before current year | 271 |  | 271 |  | 286
Prior | 253 |  | 253 |  | 59
Total loans | 2,528 |  | 2,528 |  | 2,345
Consumer | All Other Consumer |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 3,548 |  | 3,548 |  | 11,612
Prior year | 8,379 |  | 8,379 |  | 6,975
Two years before current year | 4,400 |  | 4,400 |  | 3,425
Three years before current year | 2,223 |  | 2,223 |  | 2,236
Four years before current year | 1,617 |  | 1,617 |  | 1,118
Prior | 1,268 |  | 1,268 |  | 579
Revolving Loans | 7,965 |  | 7,965 |  | 5,541
Total loans | 29,400 |  | 29,400 |  | 31,486
Current period gross charge offs, 2024 |  |  |  |  | 50
Current period gross charge offs, 2023 |  |  | 102 |  | 197
Current period gross charge offs, 2022 |  |  | 71 |  | 121
Current period gross charge offs, 2021 |  |  | 53 |  | 22
Current period gross charge offs, 2020 |  |  | 24 |  | 16
Current period gross charge offs, Prior |  |  | 3 |  | 24
Current period gross charge offs, Revolving Loans |  |  | 93 |  | 182
Current period gross charge offs, Total |  |  | 346 |  | 612
Consumer | All Other Consumer | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 3,548 |  | 3,548 |  | 11,580
Prior year | 8,294 |  | 8,294 |  | 6,883
Two years before current year | 4,276 |  | 4,276 |  | 3,270
Three years before current year | 2,217 |  | 2,217 |  | 2,161
Four years before current year | 1,546 |  | 1,546 |  | 1,094
Prior | 1,245 |  | 1,245 |  | 576
Revolving Loans | 7,942 |  | 7,942 |  | 5,501
Total loans | 29,068 |  | 29,068 |  | 31,065
Consumer | All Other Consumer | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year |  |  |  |  | 32
Prior year | 85 |  | 85 |  | 92
Two years before current year | 124 |  | 124 |  | 155
Three years before current year | 6 |  | 6 |  | 75
Four years before current year | 71 |  | 71 |  | 24
Prior | 23 |  | 23 |  | 3
Revolving Loans | 23 |  | 23 |  | 40
Total loans | $ 332 |  | $ 332 |  | $ 421

X
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