Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Composition of the loans
Portfolio loans, net of unearned income	$ 7,959,382	$ 8,071,957
Loans held for sale	694	1,010
Total Loans	7,960,076	8,072,967
Interest receivable	$ 32,400	$ 33,400
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	$ 2,836,088	$ 2,921,761
Commercial loans \| Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,321,544	1,330,605
Commercial loans \| Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	391,584	365,377
Business banking
Composition of the loans
Portfolio loans, net of unearned income	1,299,414	1,315,863
Consumer loans \| Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	2,026,801	2,047,071
Consumer loans \| Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 83,951	$ 91,280

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
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-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
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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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