Loans and Credit Quality - Restructured Loans (Details) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($) contract	Dec. 31, 2019 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Portfolio loans: Interest Only	$ 46,056
Portfolio loans: Full Payment Deferral	74,337
Portfolio loans: Total	$ 120,393
Number of modifications: Interest Only \| contract	16,000
Number of modifications: Full Payment Deferral \| contract	59,000
Number of modifications: Total \| contract	75,000
New Troubled Debt Restructurings	$ 1,728
Existing Troubled Debt Restructurings	6,748
Total	8,476	$ 10,100
Accrual Status
Financing Receivable, Troubled Debt Restructuring [Line Items]
New Troubled Debt Restructurings	1,565
Existing Troubled Debt Restructurings	802
Total	2,367
Nonaccrual Status
Financing Receivable, Troubled Debt Restructuring [Line Items]
New Troubled Debt Restructurings	163
Existing Troubled Debt Restructurings	5,946
Total	6,109
Commercial \| AQR Substandard
Financing Receivable, Troubled Debt Restructuring [Line Items]
New Troubled Debt Restructurings	1,728
Commercial \| AQR Substandard \| Accrual Status
Financing Receivable, Troubled Debt Restructuring [Line Items]
New Troubled Debt Restructurings	1,565
Commercial \| AQR Substandard \| Nonaccrual Status
Financing Receivable, Troubled Debt Restructuring [Line Items]
New Troubled Debt Restructurings	$ 163

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Financing Receivable, Modifications, Non Troubled Debt, Interest

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Financing Receivable, Troubled Debt Restructuring, Existing Restructurings

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Financing Receivable, Troubled Debt Restructuring, Newly Restructured

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Financing Receivables, Modifications, Non Troubled Debt, Amount

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Financing Receivables, Modifications, Non Troubled Debt, Full Payment Deferral

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Financing Receivables, Modifications, Non Troubled Debt, Interest, Number Of Contracts

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Financing Receivables, Modifications, Non-Troubled Debt, Number Of Contracts

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Amount of financing receivable modified as troubled debt restructuring.

+ 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

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-SubTopic 40
-Section 50
-Paragraph 4
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