Asset Quality - Schedule of Financial Effects of Modifications to Borrowers Experiencing Financial Difficulty (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Total commercial real estate loans \| Commercial and Industrial
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	(25.53%)	(30.00%)	(25.53%)	(20.24%)
Weighted-average Term Extension (in years)	1 year 29 days	7 months 24 days	1 year 1 month 2 days	7 months 20 days
Total commercial real estate loans \| Commercial mortgage
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	0.00%	0.00%	0.00%	0.00%
Weighted-average Term Extension (in years)	1 year 1 month 2 days	1 year 8 months 26 days	9 months 29 days	1 year 5 months 8 days
Total commercial real estate loans \| Construction
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change				0.00%
Weighted-average Term Extension (in years)				6 months
Total consumer loans \| Real estate — residential mortgage
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	(2.22%)	(2.06%)	(2.33%)	(1.69%)
Weighted-average Term Extension (in years)	10 years 4 months 17 days	6 years 1 month 6 days	9 years 10 days	5 years 7 months 2 days
Total consumer loans \| Home equity loans
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	(1.55%)	(2.06%)	(3.30%)	(2.57%)
Weighted-average Term Extension (in years)	3 years 3 months 14 days	5 years 11 months 15 days	8 years 18 days	6 years 4 months 17 days
Total consumer loans \| Other consumer loans
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	(2.36%)	(3.25%)	(4.80%)	(3.38%)
Weighted-average Term Extension (in years)	7 months 9 days	9 months 18 days	9 months	8 months 23 days
Total consumer loans \| Credit cards
Financing Receivable, Modified [Line Items]
Weighted-average Interest Rate Change	(20.07%)	(2.08%)	(20.31%)	(5.24%)
Weighted-average Term Extension (in years)	3 months	3 months	6 months	6 months

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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