Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Composition of the loans
Portfolio loans, net of unearned income	$ 7,689,054	$ 7,653,341
Loans held for sale	307	153
Total Loans	7,689,361	7,653,494
Interest receivable	$ 33,600	$ 35,300
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	$ 2,660,816	$ 2,659,135
Commercial Loans \| Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,363,477	1,436,183
Commercial Loans \| Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	374,299	350,583
Business Banking
Composition of the loans
Portfolio loans, net of unearned income	1,291,080	1,360,765
Consumer Loans \| Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	1,894,147	1,731,778
Consumer Loans \| Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 105,235	$ 114,897

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

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- Definition

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

+ References

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-Topic 326
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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

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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
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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.

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