Fair Value Disclosures - Fair value on a recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available-for-sale:
Debt investment securities	$ 36,078	$ 36,975
Residential mortgage-backed - US agency and GSEs
Securities available-for-sale:
Debt investment securities	30	33
Corporate bonds
Securities available-for-sale:
Debt investment securities	19,089	18,043
Recurring
Equity securities:
Investments, Fair Value Disclosure, Total	36,416	37,325
Recurring \| Residential mortgage-backed - US agency and GSEs
Securities available-for-sale:
Debt investment securities	30	33
Recurring \| Corporate bonds
Securities available-for-sale:
Debt investment securities	19,089	18,043
Recurring \| Municipal bonds
Securities available-for-sale:
Debt investment securities	16,959	18,899
Recurring \| Large cap equity mutual fund
Equity securities:
Equity investment securities, at fair value	44	45
Recurring \| Other mutual funds
Equity securities:
Equity investment securities, at fair value	294	305
Level 1
Equity securities:
Equity investment securities, at fair value	338	350
Level 1 \| Recurring
Equity securities:
Investments, Fair Value Disclosure, Total	338	350
Level 1 \| Recurring \| Large cap equity mutual fund
Equity securities:
Equity investment securities, at fair value	44	45
Level 1 \| Recurring \| Other mutual funds
Equity securities:
Equity investment securities, at fair value	294	305
Level 2
Securities available-for-sale:
Debt investment securities	33,573	33,965
Level 2 \| Recurring
Equity securities:
Investments, Fair Value Disclosure, Total	33,573	33,965
Level 2 \| Recurring \| Residential mortgage-backed - US agency and GSEs
Securities available-for-sale:
Debt investment securities	30	33
Level 2 \| Recurring \| Corporate bonds
Securities available-for-sale:
Debt investment securities	19,089	18,043
Level 2 \| Recurring \| Municipal bonds
Securities available-for-sale:
Debt investment securities	14,454	15,889
Level 3
Securities available-for-sale:
Debt investment securities	2,505	3,010
Level 3 \| Recurring
Equity securities:
Investments, Fair Value Disclosure, Total	2,505	3,010
Level 3 \| Recurring \| Municipal bonds
Securities available-for-sale:
Debt investment securities	$ 2,505	$ 3,010

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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-Publisher FASB
-Name Accounting Standards Codification
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