Assets measured at fair value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value Inputs Level 1 S A L [Member]
Assets at fair value on a recurring basis
U.S. Treasury
U.S. Government Agency notes
Municipal bonds
U.S. Government agencies and U.S. Government-sponsored enterprises
U.S. Government agencies
Corporate bonds
Securities available-for-sale
CRA mutual funds	907	917
Derivative financial instruments
Assets at fair value on a non-recurring basis
Assets held for sale 1	700
Fair Value Inputs Level 2 S A L [Member]
Assets at fair value on a recurring basis
U.S. Treasury	10,302
U.S. Government Agency notes	32,274	7,851
Municipal bonds	39,605	27,617
U.S. Government agencies and U.S. Government-sponsored enterprises	67,179	36,573
U.S. Government agencies	15,011	17,454
Corporate bonds	11,197	8,916
Securities available-for-sale	175,568	98,411
CRA mutual funds
Derivative financial instruments	4	4
Assets at fair value on a non-recurring basis
Assets held for sale 1
Fair Value Inputs Level 3 S A L [Member]
Assets at fair value on a recurring basis
U.S. Treasury
U.S. Government Agency notes
Municipal bonds
U.S. Government agencies and U.S. Government-sponsored enterprises
U.S. Government agencies
Corporate bonds
Securities available-for-sale
CRA mutual funds
Derivative financial instruments
Assets at fair value on a non-recurring basis
Assets held for sale 1
Fair Value Inputs Level 12 And 3 S A L [Member]
Assets at fair value on a recurring basis
U.S. Treasury	10,302
U.S. Government Agency notes	32,274	7,851
Municipal bonds	39,605	27,617
U.S. Government agencies and U.S. Government-sponsored enterprises	67,179	36,573
U.S. Government agencies	15,011	17,454
Corporate bonds	11,197	8,916
Securities available-for-sale	175,568	98,411
CRA mutual funds	907	917
Derivative financial instruments	4	$ 4
Assets at fair value on a non-recurring basis
Assets held for sale 1	$ 700

No definition available.

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- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123398962&loc=d3e400-110220

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- Definition

Amount of securities that are debt instruments (corporate or municipal bonds) that typically have long-term nominal maturities for which the interest rate is reset through an auction process.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

+ Details

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- Definition

The total of collateralized agreements including securities purchased under agreements to resell (repos), borrowed securities, and secured demand notes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 05
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=109246787&loc=d3e93640-111703

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- Definition

Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- References

No definition available.

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- References

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

+ Details

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

Bonds or similar securities issued by state, city, or local governments or the agencies operated by state, city, or local governments which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

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- Definition

Debt securities issued by a United States government agency such as Government National Mortgage Association (Ginnie Mae), Federal Home Loan Mortgage Corporation (Freddie Mac), and Federal National Mortgage Association (Fannie Mae), which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

+ Details

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