Investment securities available for sale - Summary of gross realized gains and losses to available for sale securities (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Investment securities available for sale
Gross realized gains	$ 0	$ 54,000
Gross realized losses		(42,000)
Available-for-sale Securities, Gross Realized Gain (Loss), Total	$ 0	$ 12,000

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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- Definition

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), excluding other-than-temporary impairment (OTTI).

+ References

No definition available.

+ Details

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- Definition

Amount of realized loss on 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 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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- References

No definition available.

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