Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Composition of the loans
Portfolio loans, net of unearned income	$ 7,515,918	$ 7,183,969
Loans held for sale	257	16
Total Loans	7,516,175	7,183,985
Interest receivable	34,200	28,300
Commercial Loans \| Commercial real estate
Composition of the loans
Portfolio loans, net of unearned income	2,591,189	2,538,839
Commercial Loans \| Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,424,141	1,510,392
Commercial Loans \| Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	372,839	381,963
Business Banking
Composition of the loans
Portfolio loans, net of unearned income	1,363,314	1,205,944
Consumer Loans \| Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	1,649,056	1,421,953
Consumer Loans \| Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 115,379	$ 124,878

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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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/2003/role/disclosureRef
-Topic 310
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