Available-for-sale securities (Details 2) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Cost	$ 11,109	$ 11,185
Gross Unrealized Gains	51	156
Gross Unrealized Losses	58	14
Fair Value	11,102	11,327
Mortgage-backed securities
Debt Securities, Available-for-sale [Abstract]
Cost	8,702	9,799
Gross Unrealized Gains	51	156
Gross Unrealized Losses	47	9
Fair Value	8,706	9,946
U.S. Treasury securities
Debt Securities, Available-for-sale [Abstract]
Cost	2,407	1,386
Gross Unrealized Gains	0	0
Gross Unrealized Losses	11	5
Fair Value	$ 2,396	$ 1,381

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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