Loans, Allowance for Credit Losses and Credit Quality - Financial Effects of Loan Modifications (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2023
Commercial Real Estate [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Added weighted-average contractual term to the life of the loan	2 years 10 months 24 days	1 year 9 months 18 days
% of Total Class of Financing Receivable	0.01%	0.24%
Commercial Real Estate [Member] \| Other-Than-Insignificant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
% of Total Class of Financing Receivable	0.00%	0.09%
Small Business [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Added weighted-average contractual term to the life of the loan		4 years 3 months 18 days
% of Total Class of Financing Receivable	0.00%	0.04%
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension \| Maximum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate		10.00%
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension \| Minimum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate		6.50%
Commercial And Industrial [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Added weighted-average contractual term to the life of the loan	2 months	2 months
% of Total Class of Financing Receivable	0.48%	0.97%
Commercial And Industrial [Member] \| Other-Than-Insignificant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
% of Total Class of Financing Receivable	0.00%	0.17%
Construction [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Added weighted-average contractual term to the life of the loan		2 months

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

+ Details

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- Definition

Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

+ Details

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- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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