Available-for-sale securities - Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 105,605	$ 96,547
Gross Unrealized Gains	7	178
Gross Unrealized (Losses)	(21,092)	(2,384)
Fair Value	84,520	94,341
U. S. Government agency and mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	73,480	67,850
Gross Unrealized Gains	0	24
Gross Unrealized (Losses)	(14,434)	(1,245)
Fair Value	59,046	66,629
Corporate bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	19,773	17,754
Gross Unrealized Gains	7	118
Gross Unrealized (Losses)	(5,125)	(951)
Fair Value	14,655	16,921
Subordinated notes
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	5,000	4,608
Gross Unrealized Gains	0	35
Gross Unrealized (Losses)	(398)	(17)
Fair Value	4,602	4,626
SBA loan pools
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	6,791	5,772
Gross Unrealized Gains	0	0
Gross Unrealized (Losses)	(1,073)	(169)
Fair Value	5,718	5,603
Municipal bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	561	563
Gross Unrealized Gains	0	1
Gross Unrealized (Losses)	(62)	(2)
Fair Value	$ 499	$ 562

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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