Asset Quality - Schedule of Financial Effects of Modifications to Borrowers Experiencing Financial Difficulty (Details)	3 Months Ended	12 Months Ended
Dec. 31, 2023	Dec. 31, 2023
Total commercial loans \| Commercial and Industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	(14.58%)	5.69%
Weighted-average Term Extension (in years)	4 months 17 days	7 months 2 days
Total commercial loans \| Commercial mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change		0.00%
Weighted-average Term Extension (in years)		1 year 4 months 13 days
Total consumer loans \| Real estate — residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	(1.82%)	(1.97%)
Weighted-average Term Extension (in years)	7 years 9 months	7 years 6 months 29 days
Total consumer loans \| Home equity loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	(2.48%)	(4.02%)
Weighted-average Term Extension (in years)	7 years 8 months 26 days	6 years 10 months 13 days
Total consumer loans \| Consumer direct loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	(1.17%)	(3.62%)
Weighted-average Term Extension (in years)	4 months 17 days	1 year 3 days
Total consumer loans \| Credit cards
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	(13.76%)	(14.90%)
Weighted-average Term Extension (in years)	3 months	1 year
Total consumer loans \| Consumer indirect loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average Interest Rate Change	0.00%	(3.05%)
Weighted-average Term Extension (in years)	5 months 1 day	6 months 3 days

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.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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