Loans Allowance for Loan Losses and Credit Quality (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		$ 39,242
Impaired Financing Receivable, with Related Allowance, Recorded Investment		10,386
Impaired Financing Receivable, Recorded Investment		49,628
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		56,605
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		11,535
Impaired Financing Receivable, Unpaid Principal Balance		68,140
Impaired Financing Receivable, Related Allowance		980
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		980
Average Recorded Investment		49,077
Average Recorded Investment		10,605
Impaired Financing Receivable, Average Recorded Investment		59,682
Interest Income Recognized	$ 1,090
Interest Income Recognized		447
Interest Income Recognized		1,537
With Allowance Recorded [Member] \| Commercial And Industrial [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		670
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		670
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		126
Average Recorded Investment		718
Interest Income Recognized		29
With Allowance Recorded [Member] \| Commercial Real Estate [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		2,124
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		2,124
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		48
Average Recorded Investment		2,176
Interest Income Recognized		122
With Allowance Recorded [Member] \| Small Business [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		68
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		105
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		8
Average Recorded Investment		74
Interest Income Recognized		2
With Allowance Recorded [Member] \| Residential Real Estate [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		6,252
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		7,163
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		637
Average Recorded Investment		6,326
Interest Income Recognized		239
With Allowance Recorded [Member] \| Home Equity Loan [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		1,184
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		1,382
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		156
Average Recorded Investment		1,214
Interest Income Recognized		52
With Allowance Recorded [Member] \| Consumer Loan [Member]
Loans Allowance for Loan Losses and Credit Quality [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		88
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		91
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		5
Average Recorded Investment		97
Interest Income Recognized		$ 3

Loans Allowance for Loan Losses and Credit Quality [Line Items]

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.

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