Investment securities available for sale - Amortized cost and fair value of investment securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 95,606	$ 40,255
Gross Unrealized Gains	414	776
Gross Unrealized Losses	(1,321)	(187)
Fair Value	94,699	40,844
U.S. Government agencies obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	41,513	8,048
Gross Unrealized Gains	22	94
Gross Unrealized Losses	(536)
Fair Value	40,999	8,142
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	40,806	23,412
Gross Unrealized Gains	302	645
Gross Unrealized Losses	(613)	(51)
Fair Value	40,495	24,006
Municipals
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,271
Gross Unrealized Losses	(62)
Fair Value	2,209
Fixed-to-floating rate subordinated notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,016	8,795
Gross Unrealized Gains	90	37
Gross Unrealized Losses	(110)	(136)
Fair Value	$ 10,996	$ 8,696

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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Amount 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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