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Segment Reporting - Results for Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2022 | Dec. 31, 2021
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income | $ 11,621 | $ 10,670 | $ 9,525 | $ 9,381 | $ 9,987 | $ 10,030 | $ 10,059 | $ 9,845 | $ 41,197 | $ 39,921
Total interest expense | 1,730 | 1,155 | 699 | 672 | 727 | 695 | 747 | 781 | 4,256 | 2,950
Net interest income | 9,891 | 9,515 | 8,826 | 8,709 | 9,260 | 9,335 | 9,312 | 9,064 | 36,941 | 36,971
Provision |  |  |  |  |  |  |  |  | 3,308 | 2,010
Net interest income after provision for loan and lease losses | 9,364 | 8,350 | 7,931 | 7,988 | 8,767 | 8,717 | 8,814 | 8,663 | 33,633 | 34,961
Total non-interest income | 678 | 1,088 | 856 | 829 | 865 | 896 | 809 | 951 | 3,451 | 3,521
Total non-interest expense | 7,106 | 7,032 | 6,878 | 7,056 | 7,414 | 8,547 | 8,399 | 8,396 | 28,072 | 32,756
Income before income taxes | 2,936 | 2,406 | 1,909 | 1,761 | 2,218 | 1,066 | 1,224 | 1,218 | 9,012 | 5,726
Provision for income taxes | 708 | 546 | 494 | 400 | 507 | 229 | 271 | 268 | 2,148 | 1,275
Net income (loss) | 2,228 | $ 1,860 | $ 1,415 | $ 1,361 | 1,711 | $ 837 | $ 953 | $ 950 | 6,864 | 4,451
Total assets | 994,667 |  |  |  | 958,302 |  |  |  | 994,667 | 958,302
Total investment securities | 132,657 |  |  |  | 134,319 |  |  |  | 132,657 | 134,319
Total loans, net | 764,451 |  |  |  | 700,030 |  |  |  | 764,451 | 700,030
Goodwill and core deposit intangible, net | 7,801 |  |  |  | 8,069 |  |  |  | 7,801 | 8,069
Fixed asset additions |  |  |  |  |  |  |  |  | 1,262 | 822
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 1,614 | 1,692
Total interest income from external customers |  |  |  |  |  |  |  |  | 41,197 | 39,921
Intersegment Eliminations [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | (1,034) | (1,642)
Total interest expense |  |  |  |  |  |  |  |  | (1,034) | (1,642)
Total non-interest income |  |  |  |  |  |  |  |  | (8,379) | (5,958)
Total non-interest expense |  |  |  |  |  |  |  |  | (195) | (452)
Income before income taxes |  |  |  |  |  |  |  |  | (8,184) | (5,506)
Net income (loss) |  |  |  |  |  |  |  |  | (8,184) | (5,506)
Total assets | (124,904) |  |  |  | (150,441) |  |  |  | (124,904) | (150,441)
Total loans, net | (18,300) |  |  |  | (39,069) |  |  |  | (18,300) | (39,069)
Investment in subsidiaries | (93,414) |  |  |  | (95,172) |  |  |  | (93,414) | (95,172)
Total interest income from affiliates |  |  |  |  |  |  |  |  | (1,034) | (1,642)
FUSB [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total loans, net | 745,641 |  |  |  | 660,533 |  |  |  | 745,641 | 660,533
FUSB [Member] | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 37,510 | 32,537
Total interest expense |  |  |  |  |  |  |  |  | 3,803 | 2,842
Net interest income |  |  |  |  |  |  |  |  | 33,707 | 29,695
Provision |  |  |  |  |  |  |  |  | 1,338 | 1,515
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | 32,369 | 28,180
Total non-interest income |  |  |  |  |  |  |  |  | 3,535 | 3,206
Total non-interest expense |  |  |  |  |  |  |  |  | 25,278 | 25,188
Income before income taxes |  |  |  |  |  |  |  |  | 10,626 | 6,198
Provision for income taxes |  |  |  |  |  |  |  |  | 2,475 | 1,305
Net income (loss) |  |  |  |  |  |  |  |  | 8,151 | 4,893
Total assets | 998,727 |  |  |  | 961,572 |  |  |  | 998,727 | 961,572
Total investment securities | 132,657 |  |  |  | 134,238 |  |  |  | 132,657 | 134,238
Total loans, net | 763,941 |  |  |  | 699,600 |  |  |  | 763,941 | 699,600
Goodwill and core deposit intangible, net | 7,801 |  |  |  | 8,069 |  |  |  | 7,801 | 8,069
Fixed asset additions |  |  |  |  |  |  |  |  | 1,262 | 816
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 1,579 | 1,613
Total interest income from external customers |  |  |  |  |  |  |  |  | 36,481 | 30,902
Total interest income from affiliates |  |  |  |  |  |  |  |  | 1,029 | 1,635
ALC [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total loans, net | 18,810 |  |  |  | 39,497 |  |  |  | 18,810 | 39,497
ALC [Member] | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 4,716 | 9,019
Total interest expense |  |  |  |  |  |  |  |  | 1,029 | 1,635
Net interest income |  |  |  |  |  |  |  |  | 3,687 | 7,384
Provision |  |  |  |  |  |  |  |  | 1,970 | 495
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | 1,717 | 6,889
Total non-interest income |  |  |  |  |  |  |  |  | 204 | 576
Total non-interest expense |  |  |  |  |  |  |  |  | 1,751 | 6,599
Income before income taxes |  |  |  |  |  |  |  |  | 170 | 866
Provision for income taxes |  |  |  |  |  |  |  |  | 45 | 221
Net income (loss) |  |  |  |  |  |  |  |  | 125 | 645
Total assets | 19,772 |  |  |  | 40,924 |  |  |  | 19,772 | 40,924
Total loans, net | 18,810 |  |  |  | 39,499 |  |  |  | 18,810 | 39,499
Fixed asset additions |  |  |  |  |  |  |  |  |  | 6
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 35 | 79
Total interest income from external customers |  |  |  |  |  |  |  |  | 4,716 | 9,019
Other Segments [Member] | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 5 | 7
Total interest expense |  |  |  |  |  |  |  |  | 458 | 115
Net interest income |  |  |  |  |  |  |  |  | (453) | (108)
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | (453) | (108)
Total non-interest income |  |  |  |  |  |  |  |  | 8,091 | 5,697
Total non-interest expense |  |  |  |  |  |  |  |  | 1,238 | 1,421
Income before income taxes |  |  |  |  |  |  |  |  | 6,400 | 4,168
Provision for income taxes |  |  |  |  |  |  |  |  | (372) | (251)
Net income (loss) |  |  |  |  |  |  |  |  | 6,772 | 4,419
Total assets | 101,072 |  |  |  | 106,247 |  |  |  | 101,072 | 106,247
Total investment securities |  |  |  |  | 81 |  |  |  |  | 81
Investment in subsidiaries | $ 93,414 |  |  |  | $ 95,172 |  |  |  | 93,414 | 95,172
Total interest income from affiliates |  |  |  |  |  |  |  |  | $ 5 | $ 7

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