Available-for-sale securities (Details 2) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Available-for-sale securities [Abstract]
Cost	$ 11,466	$ 11,109	$ 11,345
Gross Unrealized Gains	3	51	155
Gross Unrealized Losses	373	58	24
Fair Value	11,096	11,102	11,476
Mortgage-backed securities
Available-for-sale securities [Abstract]
Cost	8,778	8,702	8,709
Gross Unrealized Gains	3	51	155
Gross Unrealized Losses	310	47	10
Fair Value	8,471	8,706	8,854
U.S. Treasury securities
Available-for-sale securities [Abstract]
Cost	2,688	2,407	2,636
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	63	11	14
Fair Value	$ 2,625	$ 2,396	$ 2,622

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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