Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Composition of the loans
Portfolio loans, net of unearned income	$ 8,071,957	$ 7,742,958
Loans held for sale	1,010	0
Total Loans	8,072,967	7,742,958
Interest receivable	$ 33,400	$ 32,700
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Commercial loans \| Commercial real estate
Composition of the loans
Portfolio loans, net of unearned income	$ 2,921,761	$ 2,708,531
Commercial loans \| Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,330,605	1,351,637
Commercial loans \| Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	365,377	341,266
Business banking
Composition of the loans
Portfolio loans, net of unearned income	1,315,863	1,303,258
Consumer loans \| Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	2,047,071	1,933,509
Consumer loans \| Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 91,280	$ 104,757

Financing Receivable, Before Allowance For Credit Loss And Held For Sale, Not Part Of Disposal Group

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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