Loans, net and allowance for loan losses - Net Deferred Loan Costs (Details)		12 Months Ended
Mar. 27, 2020 USD ($)	Dec. 31, 2021 USD ($) loan	Mar. 31, 2022 USD ($)
Net deferred loan costs		$ 1,567,000	$ 618,000
Loans		2,329,173,000	2,397,681,000
PPP
Net deferred loan costs		1,659,000	740,000
Loans		68,893,000	38,680,000
Fixed interest rate	$ 1.00
PPP \| Scenario, Loans Issued Before 5 June 2020 [Member]
Term of paycheck protection program	2 years
Deferral term of paycheck protection program	24 months
PPP \| Scenario, Loans Issued After 5 June 2020 [Member]
Term of paycheck protection program	5 years
Deferral term of paycheck protection program	60 months
PPP Two
Net deferred loan costs		$ 4,300,000
Loans			25,444,000
Number of loans \| loan		1,062
Proceeds from Sale of Loans Receivable		$ 121,600,000
PPP One
Loans			$ 13,236,000

Net deferred loan costs included in loan balances.

No definition available.

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- Definition

Deferral term of paycheck protection program loans.

+ References

No definition available.

+ Details

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- Definition

Term of paycheck protection program loans.

+ References

No definition available.

+ Details

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- Definition

The number of loans processed under the Paycheck Protection Program.

+ References

No definition available.

+ Details

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- Definition

Amount before allowance and after 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.

+ 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 http://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 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524

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- Definition

Amount of loan with fixed rate of interest.

+ References

+ Details

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- Definition

The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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