Allowance for loan losses and credit quality Narrative Data (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) loans	Sep. 30, 2018 loans	Sep. 30, 2019 USD ($) loans	Sep. 30, 2018 loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans modified within the previous twelve months that had subsequently defaulted \| loans	1	0	1	0
Recorded investment of TDR loans modified within the previous twelve months that had subsequently defaulted \| $	$ 78		$ 78

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.

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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