Loans and Leases - Loan Modifications to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 45.0	$ 107.0
% of Total Class	0.07%	0.17%
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 3 months 7 days	1 year
Amount of Principal Forgiven/Payment Deferred	$ 0.0	$ 0.0
Commercial real estate
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 6 months 7 days	1 year 7 months 6 days
Amount of Principal Forgiven/Payment Deferred	$ 0.0	$ 0.0
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	0.0
Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	44.0	107.0
Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	1.0	0.0
Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 0.0
Combination \| 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)	0 years	0 years
Combination \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average Interest Rate Reduction	0.00%	0.00%
Weighted-average Term Extension (in years)	0 years	0 years
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
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 40.0	$ 78.0
% of Total Class	0.11%	0.23%
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	40.0	78.0
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	0.0	0.0
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 4.0	$ 29.0
% of Total Class	0.03%	0.21%
Commercial real estate \| Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0	$ 0.0
Commercial real estate \| Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	4.0	29.0
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	0.0	$ 0.0
Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 1.0
% of Total Class	0.01%
Consumer Real Estate \| Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0
Consumer Real Estate \| Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	0.0
Consumer Real Estate \| Principal Forgiven/Payment Deferred
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	1.0
Consumer Real Estate \| Combination
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 0.0

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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-Name Accounting Standards Codification
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