Loans and Leases - Loan Modifications to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 47	$ 0
% of Total Class	0.10%	0.00%
Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 246	$ 123
% of Total Class	0.40%	0.20%
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 34	$ 3
% of Total Class	0.10%	0.00%
Commercial: \| Commercial real estate \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 47	$ 0
% of Total Class	0.30%	0.00%
Commercial: \| Commercial real estate \| Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	7.61%
Commercial: \| Commercial real estate \| Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	6.96%
Commercial: \| Commercial real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 124	$ 28
% of Total Class	0.90%	0.20%
Weighted average life of loans	1 year 3 months 18 days	2 years 4 months 24 days
Commercial: \| Commercial real estate \| Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 33	$ 0
% of Total Class	0.20%	0.00%
Weighted average life of loans	2 years
Commercial: \| Commercial real estate \| Combination - Term Extension and Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	7.78%
Commercial: \| Commercial real estate \| Combination - Term Extension and Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	6.82%
Commercial: \| Commercial and industrial \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 122	$ 95
% of Total Class	0.40%	0.30%
Weighted average life of loans	1 year 1 month 6 days	1 year 2 months 12 days
Commercial: \| Commercial and industrial \| Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Weighted average life of loans	1 year 2 months 12 days
Commercial: \| Commercial and industrial \| Combination - Term Extension and Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	9.19%
Commercial: \| Commercial and industrial \| Combination - Term Extension and Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	8.17%
Consumer: \| Consumer Real Estate \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Consumer: \| Consumer Real Estate \| Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	11.10%	9.87%
Consumer: \| Consumer Real Estate \| Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	6.58%	6.52%
Consumer: \| Consumer Real Estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Weighted average life of loans		22 years
Consumer: \| Consumer Real Estate \| Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Decrease from loan modification (less than)	$ 1	$ 1
Consumer: \| Consumer Real Estate \| Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 1	$ 3
% of Total Class	0.00%	0.00%
Weighted average life of loans	11 years 2 months 12 days	10 years 9 months 18 days
Consumer: \| Consumer Real Estate \| Combination - Term Extension and Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	8.43%	8.39%
Consumer: \| Consumer Real Estate \| Combination - Term Extension and Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	4.35%	3.67%
Consumer: \| Credit Card and Other \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0	$ 0
% of Total Class	0.00%	0.00%
Consumer: \| Credit Card and Other \| Interest Rate Reduction \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	17.36%	5.77%
Consumer: \| Credit Card and Other \| Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	0.00%	4.41%

Amount of increase (decrease) in amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

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-Topic 310
-SubTopic 10
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