Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Composition of the loans
Portfolio loans, net of unearned income	$ 7,836,349	$ 7,742,958
Total Loans	7,836,349	7,742,958
Interest receivable	$ 32,900	$ 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	$ 2,776,065	$ 2,708,531
Commercial Loans \| Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,331,091	1,351,637
Commercial Loans \| Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	367,869	341,266
Business Banking
Composition of the loans
Portfolio loans, net of unearned income	1,314,482	1,303,258
Consumer Loans \| Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	1,948,677	1,933,509
Consumer Loans \| Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 98,165	$ 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

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- Definition

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
-Publisher FASB
-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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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