Loans and Leases - Schedule of Loan Modifications to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 167.0	$ 327.0
% of Total Class	0.26%	0.52%
Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction		0.00%
Weighted-average Term Extension (in years)		0 years
Amount of Principal Forgiven/Payment Deferred		$ 0.0
Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	47.0
Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	142.0	246.0
Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	2.0	0.0
Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	23.0	$ 34.0
Combination \| Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction		4.08%
Weighted-average Term Extension (in years)		11 years 2 months 12 days
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 125.0	$ 122.0
% of Total Class	0.34%	0.36%
Commercial and industrial \| Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 0.0
Commercial and industrial \| Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	104.0	122.0
Commercial and industrial \| Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	0.0	0.0
Commercial and industrial \| Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	21.0	0.0
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 40.0	$ 204.0
% of Total Class	0.29%	1.46%
Commercial real estate \| Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 47.0
Commercial real estate \| Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	38.0	124.0
Commercial real estate \| Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	0.0	0.0
Commercial real estate \| Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	2.0	33.0
Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 2.0	$ 1.0
% of Total Class	0.01%	0.01%
Consumer Real Estate \| Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 0.0
Consumer Real Estate \| Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	0.0	0.0
Consumer Real Estate \| Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	2.0	0.0
Consumer Real Estate \| Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 1.0
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.00%	0.00%
Weighted-average Term Extension (in years)	1 year 1 month 13 days	1 year 1 month 6 days
Amount of Principal Forgiven/Payment Deferred	$ 0.0	$ 0.0
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.00%	0.65%
Weighted-average Term Extension (in years)	1 year 8 months 4 days	1 year 3 months 18 days
Amount of Principal Forgiven/Payment Deferred	$ 0.0	$ 0.0
Commercial \| Combination \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.04%	0.00%
Weighted-average Term Extension (in years)	1 year 3 months 7 days	0 years
Commercial \| Combination \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.67%	0.96%
Weighted-average Term Extension (in years)	4 years 7 months 17 days	2 years
Consumer \| Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.00%
Weighted-average Term Extension (in years)	0 years
Amount of Principal Forgiven/Payment Deferred	$ 2.0
Consumer \| Combination \| Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.00%
Weighted-average Term Extension (in years)	0 years

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