Loans and allowance for loan losses (Detail Textuals) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loan	$ 1,716	$ 1,774
Number of loans default \| Loan	3	3
Loan modified as default		$ 19
Number of charge off loans \| Loan		1
Balance of capitalized servicing rights	$ 2,203	$ 2,278
Aggregate balances of loans serviced to third party	261,559	255,892
Home equity loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loan	$ 117
Number of loans default \| Loan	2
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loan	$ 117
Number of loans default \| Loan	2
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balances of loans held for sale	$ 838	$ 888

Represents the number of charge off loans.

No definition available.

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- Definition

Represents amount of outstanding balance of loan serviced for third party.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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