Loans and Leases - Modifications to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 0.0
% of Total Class	0.00%	0.00%
Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 107.0	$ 83.0
% of Total Class	0.20%	0.10%
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 0.0
% of Total Class	0.00%	0.00%
Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 1.0
% of Total Class	0.00%	0.00%
Consumer: \| Consumer Real Estate \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 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	9.35%	9.95%
Consumer: \| Consumer Real Estate \| Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans	3.00%	6.75%
Consumer: \| Consumer Real Estate \| Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 0.0
% of Total Class	0.00%	0.00%
Decrease from loan modification (less than)	$ 1.0	$ 1.0
Consumer: \| Consumer Real Estate \| Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 1.0
% of Total Class	0.00%	0.00%
Weighted average life of loans	11 years 4 months 24 days	18 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	8.88%	6.43%
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	3.16%	3.69%
Consumer: \| Credit Card and Other \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 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		20.50%
Consumer: \| Credit Card and Other \| Interest Rate Reduction \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average interest rate of loans		0.00%
Commercial: \| Commercial and industrial \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 78.0	$ 64.0
% of Total Class	0.20%	0.20%
Weighted average life of loans	1 year	1 year 4 months 24 days
Commercial: \| Commercial and industrial \| Combination - Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 0.0	$ 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	9.00%
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	8.00%
Commercial: \| Commercial real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 29.0	$ 19.0
% of Total Class	0.20%	0.10%
Weighted average life of loans	1 year 7 months 6 days	9 months 18 days

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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