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Segment Reporting - Results for Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income | $ 10,204 | $ 9,996 | $ 9,780 | $ 10,397 | $ 10,825 | $ 11,027 | $ 10,923 | $ 10,813 | $ 40,377 | $ 43,588
Total interest expense | 912 | 1,031 | 1,157 | 1,511 | 1,636 | 1,680 | 1,690 | 1,640 | 4,611 | 6,646
Net interest income | 9,292 | 8,965 | 8,623 | 8,886 | 9,189 | 9,347 | 9,233 | 9,173 | 35,766 | 36,942
Provision |  |  |  |  |  |  |  |  | 2,945 | 2,714
Net interest income after provision for loan and lease losses | 8,823 | 7,919 | 7,773 | 8,306 | 8,473 | 8,464 | 8,518 | 8,773 | 32,821 | 34,228
Total non-interest income | 1,008 | 1,375 | 1,330 | 1,297 | 1,396 | 1,414 | 1,291 | 1,265 | 5,010 | 5,366
Total non-interest expense | 8,477 | 8,747 | 8,581 | 8,494 | 8,279 | 8,546 | 8,504 | 8,453 | 34,299 | 33,782
Income before income taxes |  |  |  |  |  |  |  |  | 3,532 | 5,812
Provision for income taxes | 309 | 136 | 118 | 262 | 381 | 214 | 300 | 351 | 825 | 1,246
Net income (loss) | 1,045 | $ 411 | $ 404 | $ 847 | 1,209 | $ 1,118 | $ 1,005 | $ 1,234 | 2,707 | 4,566
Total assets | 890,511 |  |  |  | 788,738 |  |  |  | 890,511 | 788,738
Total investment securities | 91,422 |  |  |  | 108,356 |  |  |  | 91,422 | 108,356
Total loans, net | 638,374 |  |  |  | 545,243 |  |  |  | 638,374 | 545,243
Goodwill and core deposit intangible, net | 8,410 |  |  |  | 8,825 |  |  |  | 8,410 | 8,825
Fixed asset additions |  |  |  |  |  |  |  |  | 955 | 3,184
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 1,684 | 1,609
Total interest income from external customers |  |  |  |  |  |  |  |  | 40,377 | 43,588
Intersegment Eliminations [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | (2,876) | (5,078)
Total interest expense |  |  |  |  |  |  |  |  | (2,876) | (5,078)
Total non-interest income |  |  |  |  |  |  |  |  | (4,334) | (6,141)
Total non-interest expense |  |  |  |  |  |  |  |  | (582) | (651)
Income before income taxes |  |  |  |  |  |  |  |  | (3,752) | (5,490)
Net income (loss) |  |  |  |  |  |  |  |  | (3,752) | (5,490)
Total assets | (150,512) |  |  |  | (201,467) |  |  |  | (150,512) | (201,467)
Total loans, net | (47,700) |  |  |  | (95,768) |  |  |  | (47,700) | (95,768)
Investment in subsidiaries | (86,102) |  |  |  | (84,186) |  |  |  | (86,102) | (84,186)
Total interest income from affiliates |  |  |  |  |  |  |  |  | (2,876) | (5,078)
FUSB [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total loans, net | 585,296 |  |  |  | 438,710 |  |  |  | 585,296 | 438,710
FUSB [Member] | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 31,834 | 30,921
Total interest expense |  |  |  |  |  |  |  |  | 4,632 | 6,670
Net interest income |  |  |  |  |  |  |  |  | 27,202 | 24,251
Provision |  |  |  |  |  |  |  |  | 2,206 | 788
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | 24,996 | 23,463
Total non-interest income |  |  |  |  |  |  |  |  | 4,531 | 4,559
Total non-interest expense |  |  |  |  |  |  |  |  | 25,180 | 23,065
Income before income taxes |  |  |  |  |  |  |  |  | 4,347 | 4,957
Provision for income taxes |  |  |  |  |  |  |  |  | 930 | 977
Net income (loss) |  |  |  |  |  |  |  |  | 3,417 | 3,980
Total assets | 893,430 |  |  |  | 789,620 |  |  |  | 893,430 | 789,620
Total investment securities | 91,342 |  |  |  | 108,276 |  |  |  | 91,342 | 108,276
Total loans, net | 632,996 |  |  |  | 534,478 |  |  |  | 632,996 | 534,478
Goodwill and core deposit intangible, net | 8,410 |  |  |  | 8,825 |  |  |  | 8,410 | 8,825
Fixed asset additions |  |  |  |  |  |  |  |  | 870 | 2,948
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 1,563 | 1,464
Total interest income from external customers |  |  |  |  |  |  |  |  | 28,979 | 25,867
Total interest income from affiliates |  |  |  |  |  |  |  |  | 2,855 | 5,054
ALC [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total loans, net | 53,078 |  |  |  | 106,533 |  |  |  | 53,078 | 106,533
ALC [Member] | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 11,397 | 17,719
Total interest expense |  |  |  |  |  |  |  |  | 2,855 | 5,054
Net interest income |  |  |  |  |  |  |  |  | 8,542 | 12,665
Provision |  |  |  |  |  |  |  |  | 739 | 1,926
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | 7,803 | 10,739
Total non-interest income |  |  |  |  |  |  |  |  | 752 | 909
Total non-interest expense |  |  |  |  |  |  |  |  | 8,136 | 9,599
Income before income taxes |  |  |  |  |  |  |  |  | 419 | 2,049
Provision for income taxes |  |  |  |  |  |  |  |  | 125 | 516
Net income (loss) |  |  |  |  |  |  |  |  | 294 | 1,533
Total assets | 55,727 |  |  |  | 110,374 |  |  |  | 55,727 | 110,374
Total loans, net | 53,078 |  |  |  | 106,533 |  |  |  | 53,078 | 106,533
Fixed asset additions |  |  |  |  |  |  |  |  | 85 | 236
Depreciation and amortization expense |  |  |  |  |  |  |  |  | 121 | 145
Total interest income from external customers |  |  |  |  |  |  |  |  | 11,397 | 17,719
Other Segments | Operating Segments [Member] |  |  |  |  |  |  |  |  |  |
Segment Reporting Revenue Reconciling Item [Line Items] |  |  |  |  |  |  |  |  |  |
Total interest income |  |  |  |  |  |  |  |  | 22 | 26
Net interest income |  |  |  |  |  |  |  |  | 22 | 26
Net interest income after provision for loan and lease losses |  |  |  |  |  |  |  |  | 22 | 26
Total non-interest income |  |  |  |  |  |  |  |  | 4,061 | 6,039
Total non-interest expense |  |  |  |  |  |  |  |  | 1,565 | 1,769
Income before income taxes |  |  |  |  |  |  |  |  | 2,518 | 4,296
Provision for income taxes |  |  |  |  |  |  |  |  | (230) | (247)
Net income (loss) |  |  |  |  |  |  |  |  | 2,748 | 4,543
Total assets | 91,866 |  |  |  | 90,211 |  |  |  | 91,866 | 90,211
Total investment securities | 80 |  |  |  | 80 |  |  |  | 80 | 80
Investment in subsidiaries | $ 86,102 |  |  |  | $ 84,186 |  |  |  | 86,102 | 84,186
Total interest income from external customers |  |  |  |  |  |  |  |  | 1 | 2
Total interest income from affiliates |  |  |  |  |  |  |  |  | $ 21 | $ 24

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