Loans and Allowance for Credit Losses - Financial Impact of Modifications (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2023
Commercial Loans \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in Months)	9 months	7 months
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Commercial Loans \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in Months)	3 months	9 months
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Commercial Loans \| Commercial construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in Months)	5 months	5 months
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Business banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in Months)	5 months	5 months
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Consumer Loans \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in Months)	0 months	168 months
Weighted-Average Interest Rate Reduction	0.00%	2.00%

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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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
-Paragraph 42
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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-Section 55
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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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

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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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