Loans - Financial Effect of Modifications Made to Borrowers Experiencing Financial Difficulty (Details)	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Term Extension [Member] \| Commercial Real Estate Residential [Member]
Loans [Abstract]
Weighted-average term increased	1 year
Term Extension [Member] \| Commercial Real Estate Nonresidential [Member]
Loans [Abstract]
Weighted-average term increased		1 year 2 months 12 days
Term Extension [Member] \| Commercial Other [Member]
Loans [Abstract]
Weighted-average term increased	10 months 24 days	4 years 9 months 18 days
Term Extension [Member] \| Real Estate Mortgage [Member]
Loans [Abstract]
Weighted-average term increased	4 months 24 days	4 months 24 days
Term Extension [Member] \| Consumer Indirect [Member]
Loans [Abstract]
Weighted-average term increased	8 months 12 days	1 year
Term Extension [Member] \| Home Equity Lines [Member]
Loans [Abstract]
Weighted-average term increased		2 years 1 month 6 days
Term Extension [Member] \| Consumer Direct [Member]
Loans [Abstract]
Weighted-average term increased		1 month 6 days
Interest Rate Reduction [Member] \| Commercial Real Estate Residential [Member]
Loans [Abstract]
Weighted-average contractual interest rate		9.50%
Interest Rate Reduction [Member] \| Commercial Real Estate Nonresidential [Member]
Loans [Abstract]
Weighted-average contractual interest rate, pre-modification	2.00%
Weighted-average contractual interest rate, post-modification	2.50%
Interest Rate Reduction [Member] \| Real Estate Mortgage [Member]
Loans [Abstract]
Weighted-average contractual interest rate, pre-modification	5.40%	7.80%
Weighted-average contractual interest rate, post-modification	3.10%	4.50%
Combination - Term Extension and Interest Rate Reduction [Member] \| Commercial Real Estate Residential [Member]
Loans [Abstract]
Weighted-average contractual interest rate, pre-modification		8.90%
Weighted-average contractual interest rate, post-modification		7.50%
Weighted-average term increased		12 years 2 months 12 days
Combination - Term Extension and Interest Rate Reduction [Member] \| Commercial Other [Member]
Loans [Abstract]
Weighted-average contractual interest rate, pre-modification	11.30%	5.10%
Weighted-average contractual interest rate, post-modification	9.50%	8.00%
Weighted-average term increased	2 years 4 months 24 days	9 years 7 months 6 days
Combination - Term Extension and Interest Rate Reduction [Member] \| Real Estate Mortgage [Member]
Loans [Abstract]
Weighted-average contractual interest rate, pre-modification	3.10%	6.00%
Weighted-average contractual interest rate, post-modification	3.00%	3.00%
Weighted-average term increased	4 years 2 months 12 days	1 year 9 months 18 days
Combination - Term Extension and Interest Rate Reduction [Member] \| Home Equity Lines [Member]
Loans [Abstract]
Weighted-average term increased	7 years 1 month 6 days
Weighted-average contractual interest rate	6.80%
Combination - Term Extension and Payment Change Financial Impact [Member] \| Commercial Real Estate Nonresidential [Member]
Loans [Abstract]
Weighted-average term increased	3 months 18 days
Combination - Term Extension and Payment Change Financial Impact [Member] \| Real Estate Mortgage [Member]
Loans [Abstract]
Weighted-average term increased	5 years
Combination - Term Extension and Payment Change Financial Impact [Member] \| Consumer Indirect [Member]
Loans [Abstract]
Weighted-average term increased	2 years 1 month 6 days

Weighted average interest rate of modified financing receivable.

No definition available.

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- Definition

Weighted-average interest rate, after modification, of modified financing receivable.

+ References

No definition available.

+ Details

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- Definition

Weighted-average interest rate, before modification, of modified financing receivable.

+ References

No definition available.

+ Details

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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/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
-Paragraph 42
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 42
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-Publisher FASB
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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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