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Loans and Loans Held for Sale - Restructured Loans By Segment and Type of Concession (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) loan	Mar. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	14	6
Pre-Modification Outstanding Recorded Investment	$ 6,914	$ 1,996
Post-Modification Outstanding Recorded Investment	6,865	1,897
Bankruptcy
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	341	78
Forbearance
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	80	0
Extend Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	821	1,891
Modify Rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Modify Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 5,623	$ 27
Commercial real estate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Commercial real estate | Bankruptcy | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial real estate | Forbearance | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial real estate | Extend Maturity | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial real estate | Modify Rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial real estate | Modify Payments | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Commercial and industrial | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	2	0
Pre-Modification Outstanding Recorded Investment	$ 6,304	$ 0
Post-Modification Outstanding Recorded Investment	6,296	0
Commercial and industrial | Bankruptcy | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial and industrial | Forbearance | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial and industrial | Extend Maturity | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	821	0
Commercial and industrial | Modify Rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial and industrial | Modify Payments | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 5,475	$ 0
Commercial construction | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 1,891
Post-Modification Outstanding Recorded Investment	0	1,806
Commercial construction | Bankruptcy | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial construction | Forbearance | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial construction | Extend Maturity | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	1,891
Commercial construction | Modify Rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Commercial construction | Modify Payments | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Business banking | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Business banking | Bankruptcy | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Business banking | Forbearance | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Business banking | Extend Maturity | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Business banking | Modify Rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Business banking | Modify Payments | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Consumer real estate | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	11	5
Pre-Modification Outstanding Recorded Investment	$ 609	$ 105
Post-Modification Outstanding Recorded Investment	568	91
Consumer real estate | Bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	340	78
Consumer real estate | Forbearance | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	80	0
Consumer real estate | Extend Maturity | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Consumer real estate | Modify Rate | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Consumer real estate | Modify Payments | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 148	$ 27
Other consumer | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | loan	1	0
Pre-Modification Outstanding Recorded Investment	$ 1	$ 0
Post-Modification Outstanding Recorded Investment	1	0
Other consumer | Bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	1	0
Other consumer | Forbearance | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Other consumer | Extend Maturity | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Other consumer | Modify Rate | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	0	0
Other consumer | Modify Payments | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0

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-Publisher FASB
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