Credit quality segments of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Totals	$ 1,066,216	$ 1,066,750
Allowance For Loan And Lease Losses Collectively Evaluated Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	1,051,041	1,046,614
Potential problem loans 1	21,515	25,016
Impaired loans
Unallocated allowance
Totals	1,072,556	1,071,630
Allowance For Loan And Lease Losses Collectively Evaluated Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	10,740	10,456
Potential problem loans 1	1,282	1,529
Impaired loans
Unallocated allowance	867	881
Totals	12,889	12,866
Allowance For Loan And Lease Losses Individually Evaluated Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans
Potential problem loans 1
Impaired loans	5,814	7,797
Unallocated allowance
Totals	5,814	7,797
Allowance For Loan And Lease Losses Individually Evaluated Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans
Potential problem loans 1
Impaired loans	26	96
Unallocated allowance
Totals	26	96
Allowance For Loan And Lease Losses Total Portfolio Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	1,051,041	1,046,614
Potential problem loans 1	21,515	25,016
Impaired loans	5,814	7,797
Unallocated allowance
Totals	1,078,370	1,079,427
Allowance For Loan And Lease Losses Total Portfolio Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	10,740	10,456
Potential problem loans 1	1,282	1,529
Impaired loans	26	96
Unallocated allowance	867	881
Totals	$ 12,915	$ 12,962

Amount of allowance for credit loss on receivable, classified as other and current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which interest is continuing to be earned or accrued.

+ References

No definition available.

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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- Definition

Amount of loan with fixed rate of interest.

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