Allowance for Loan Losses and Credit Quality New Troubled Debt Restructure Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Residential loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| loan	8	1
Pre-Modification Outstanding Recorded Investment	$ 547	$ 77
Post-Modification Outstanding Recorded Investment	$ 549	$ 79
Commercial loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| loan	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 15
Post-Modification Outstanding Recorded Investment	$ 0	$ 15

Number of financing receivables that have been modified by troubled debt restructurings during the reporting period.

No definition available.

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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

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

+ Details

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

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- Details

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