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Allowance for Credit Losses - Credit risk profile of loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Nonperforming loans past due |  |  | 90 days |  |
Current period gross charge offs, Total | $ 3,601 | $ 5,653 | $ 11,520 | $ 11,318 |
Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 284,730 |  | 284,730 |  | $ 424,209
Prior year | 344,246 |  | 344,246 |  | 217,824
Two years before current year | 163,564 |  | 163,564 |  | 145,349
Three years before current year | 104,841 |  | 104,841 |  | 54,134
Four years before current year | 37,689 |  | 37,689 |  | 35,258
Prior | 136,933 |  | 136,933 |  | 129,134
Revolving Loans | 70,875 |  | 70,875 |  | 69,873
Total loans | 1,142,878 |  | 1,142,878 |  | 1,075,781
Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 66 |  | 66 |  | 937
Prior year | 1,409 |  | 1,409 |  | 990
Two years before current year | 1,042 |  | 1,042 |  | 681
Three years before current year | 958 |  | 958 |  | 932
Four years before current year | 694 |  | 694 |  | 366
Prior | 1,852 |  | 1,852 |  | 2,040
Revolving Loans | 3 |  | 3 |  | 178
Total loans | 6,024 |  | 6,024 |  | 6,124
Total other loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 284,796 |  | 284,796 |  | 425,146
Prior year | 345,655 |  | 345,655 |  | 218,814
Two years before current year | 164,606 |  | 164,606 |  | 146,030
Three years before current year | 105,799 |  | 105,799 |  | 55,066
Four years before current year | 38,383 |  | 38,383 |  | 35,624
Prior | 138,785 |  | 138,785 |  | 131,174
Revolving Loans | 70,878 |  | 70,878 |  | 70,051
Total loans | 1,148,902 |  | 1,148,902 |  | 1,081,905
Residential | First Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 35,883 |  | 35,883 |  | 71,713
Prior year | 73,022 |  | 73,022 |  | 70,197
Two years before current year | 66,344 |  | 66,344 |  | 45,080
Three years before current year | 40,973 |  | 40,973 |  | 17,109
Four years before current year | 16,197 |  | 16,197 |  | 20,358
Prior | 122,845 |  | 122,845 |  | 119,270
Revolving Loans | 1,970 |  | 1,970 |  | 3,245
Total loans | 357,234 |  | 357,234 |  | 346,972
Current period gross charge offs, Prior |  |  | 156 |  |
Current period gross charge offs, Total |  |  | 156 |  |
Residential | First Liens | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 35,883 |  | 35,883 |  | 71,607
Prior year | 72,998 |  | 72,998 |  | 70,197
Two years before current year | 65,931 |  | 65,931 |  | 45,080
Three years before current year | 40,751 |  | 40,751 |  | 16,968
Four years before current year | 16,167 |  | 16,167 |  | 20,258
Prior | 121,304 |  | 121,304 |  | 117,488
Revolving Loans | 1,970 |  | 1,970 |  | 3,245
Total loans | 355,004 |  | 355,004 |  | 344,843
Residential | First Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year |  |  |  |  | 106
Prior year | 24 |  | 24 |  |
Two years before current year | 413 |  | 413 |  |
Three years before current year | 222 |  | 222 |  | 141
Four years before current year | 30 |  | 30 |  | 100
Prior | 1,541 |  | 1,541 |  | 1,782
Total loans | 2,230 |  | 2,230 |  | 2,129
Residential | Home Equity |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 141 |  | 141 |  | 1,995
Prior year | 322 |  | 322 |  | 943
Two years before current year |  |  |  |  | 86
Three years before current year | 26 |  | 26 |  | 115
Four years before current year | 94 |  | 94 |  | 69
Prior | 946 |  | 946 |  | 860
Revolving Loans | 61,829 |  | 61,829 |  | 60,051
Total loans | 63,358 |  | 63,358 |  | 64,119
Residential | Home Equity | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 141 |  | 141 |  | 1,995
Prior year | 271 |  | 271 |  | 943
Two years before current year |  |  |  |  | 8
Three years before current year | 7 |  | 7 |  | 115
Four years before current year | 94 |  | 94 |  | 55
Prior | 875 |  | 875 |  | 820
Revolving Loans | 61,829 |  | 61,829 |  | 59,875
Total loans | 63,217 |  | 63,217 |  | 63,811
Residential | Home Equity | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year | 51 |  | 51 |  |
Two years before current year |  |  |  |  | 78
Three years before current year | 19 |  | 19 |  |
Four years before current year |  |  |  |  | 14
Prior | 71 |  | 71 |  | 40
Revolving Loans |  |  |  |  | 176
Total loans | 141 |  | 141 |  | 308
Residential | Junior Liens |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 10,899 |  | 10,899 |  | 19,074
Prior year | 16,419 |  | 16,419 |  | 10,489
Two years before current year | 8,789 |  | 8,789 |  | 7,584
Three years before current year | 6,030 |  | 6,030 |  | 5,920
Four years before current year | 4,674 |  | 4,674 |  | 5,505
Prior | 9,197 |  | 9,197 |  | 6,336
Revolving Loans | 1,625 |  | 1,625 |  | 1,928
Total loans | 57,633 |  | 57,633 |  | 56,836
Current period gross charge offs, 2019 |  |  | 24 |  |
Current period gross charge offs, Prior |  |  | 12 |  |
Current period gross charge offs, Total |  |  | 36 |  |
Residential | Junior Liens | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 10,899 |  | 10,899 |  | 19,074
Prior year | 16,419 |  | 16,419 |  | 10,485
Two years before current year | 8,781 |  | 8,781 |  | 7,507
Three years before current year | 5,926 |  | 5,926 |  | 5,830
Four years before current year | 4,609 |  | 4,609 |  | 5,366
Prior | 9,037 |  | 9,037 |  | 6,195
Revolving Loans | 1,625 |  | 1,625 |  | 1,928
Total loans | 57,296 |  | 57,296 |  | 56,385
Residential | Junior Liens | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Prior year |  |  |  |  | 4
Two years before current year | 8 |  | 8 |  | 77
Three years before current year | 104 |  | 104 |  | 90
Four years before current year | 65 |  | 65 |  | 139
Prior | 160 |  | 160 |  | 141
Total loans | 337 |  | 337 |  | 451
Residential | All Other Residential |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 6,090 |  | 6,090 |  | 11,542
Prior year | 10,078 |  | 10,078 |  | 9,923
Two years before current year | 3,471 |  | 3,471 |  | 501
Three years before current year | 431 |  | 431 |  | 1,340
Four years before current year | 1,047 |  | 1,047 |  | 533
Prior | 1,600 |  | 1,600 |  | 1,600
Revolving Loans | 302 |  | 302 |  |
Total loans | 23,019 |  | 23,019 |  | 25,439
Residential | All Other Residential | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 6,090 |  | 6,090 |  | 11,542
Prior year | 10,078 |  | 10,078 |  | 9,923
Two years before current year | 3,471 |  | 3,471 |  | 501
Three years before current year | 431 |  | 431 |  | 915
Four years before current year | 653 |  | 653 |  | 498
Prior | 1,557 |  | 1,557 |  | 1,582
Revolving Loans | 302 |  | 302 |  |
Total loans | 22,582 |  | 22,582 |  | 24,961
Residential | All Other Residential | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Three years before current year |  |  |  |  | 425
Four years before current year | 394 |  | 394 |  | 35
Prior | 43 |  | 43 |  | 18
Total loans | 437 |  | 437 |  | 478
Consumer | Motor Vehicle |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 221,219 |  | 221,219 |  | 307,378
Prior year | 237,450 |  | 237,450 |  | 119,101
Two years before current year | 81,380 |  | 81,380 |  | 88,581
Three years before current year | 55,805 |  | 55,805 |  | 29,241
Four years before current year | 15,501 |  | 15,501 |  | 8,718
Prior | 3,443 |  | 3,443 |  | 2,277
Revolving Loans |  |  |  |  | 6
Total loans | 614,798 |  | 614,798 |  | 555,302
Current period gross charge offs, 2023 |  |  | 284 |  |
Current period gross charge offs, 2022 |  |  | 5,802 |  |
Current period gross charge offs, 2021 |  |  | 2,590 |  |
Current period gross charge offs, 2020 |  |  | 1,159 |  |
Current period gross charge offs, 2019 |  |  | 359 |  |
Current period gross charge offs, Prior |  |  | 161 |  |
Current period gross charge offs, Total |  |  | 10,355 |  |
Consumer | Motor Vehicle | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 221,153 |  | 221,153 |  | 306,565
Prior year | 236,144 |  | 236,144 |  | 118,362
Two years before current year | 80,919 |  | 80,919 |  | 88,144
Three years before current year | 55,243 |  | 55,243 |  | 29,004
Four years before current year | 15,316 |  | 15,316 |  | 8,652
Prior | 3,412 |  | 3,412 |  | 2,230
Revolving Loans |  |  |  |  | 6
Total loans | 612,187 |  | 612,187 |  | 552,963
Consumer | Motor Vehicle | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 66 |  | 66 |  | 813
Prior year | 1,306 |  | 1,306 |  | 739
Two years before current year | 461 |  | 461 |  | 437
Three years before current year | 562 |  | 562 |  | 237
Four years before current year | 185 |  | 185 |  | 66
Prior | 31 |  | 31 |  | 47
Total loans | 2,611 |  | 2,611 |  | 2,339
Consumer | All Other Consumer |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 10,564 |  | 10,564 |  | 13,444
Prior year | 8,364 |  | 8,364 |  | 8,161
Two years before current year | 4,622 |  | 4,622 |  | 4,198
Three years before current year | 2,534 |  | 2,534 |  | 1,341
Four years before current year | 870 |  | 870 |  | 441
Prior | 754 |  | 754 |  | 831
Revolving Loans | 5,152 |  | 5,152 |  | 4,821
Total loans | 32,860 |  | 32,860 |  | 33,237
Current period gross charge offs, 2023 |  |  | 6 |  |
Current period gross charge offs, 2022 |  |  | 83 |  |
Current period gross charge offs, 2021 |  |  | 49 |  |
Current period gross charge offs, 2020 |  |  | 30 |  |
Current period gross charge offs, 2019 |  |  | 3 |  |
Current period gross charge offs, Prior |  |  | 5 |  |
Current period gross charge offs, Revolving Loans |  |  | 95 |  |
Current period gross charge offs, Total |  |  | 271 |  |
Consumer | All Other Consumer | Performing |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year | 10,564 |  | 10,564 |  | 13,426
Prior year | 8,336 |  | 8,336 |  | 7,914
Two years before current year | 4,462 |  | 4,462 |  | 4,109
Three years before current year | 2,483 |  | 2,483 |  | 1,302
Four years before current year | 850 |  | 850 |  | 429
Prior | 748 |  | 748 |  | 819
Revolving Loans | 5,149 |  | 5,149 |  | 4,819
Total loans | 32,592 |  | 32,592 |  | 32,818
Consumer | All Other Consumer | Nonperforming Loans |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Current year |  |  |  |  | 18
Prior year | 28 |  | 28 |  | 247
Two years before current year | 160 |  | 160 |  | 89
Three years before current year | 51 |  | 51 |  | 39
Four years before current year | 20 |  | 20 |  | 12
Prior | 6 |  | 6 |  | 12
Revolving Loans | 3 |  | 3 |  | 2
Total loans | $ 268 |  | $ 268 |  | $ 419

X
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