Loans, Allowance for Credit Losses and Credit Quality - Financial Effects of Loan Modifications (Details)	3 Months Ended
Mar. 31, 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 months
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
Small Business [Member] \| Interest Rate Reduction \| Maximum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	10.00%
Small Business [Member] \| Interest Rate Reduction \| Minimum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	6.50%

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
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-Section 50
-Paragraph 42
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Paragraph 42
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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-Publisher FASB
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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

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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

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