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Loans and Allowance for Credit Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Composition of the loans
Portfolio loans, net of unearned income	$ 7,981,007	$ 7,742,958
Total Loans	7,981,007	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	$ 2,950,110	$ 2,708,531
Commercial loans | Commercial and industrial
Composition of the loans
Portfolio loans, net of unearned income	1,275,985	1,351,637
Commercial loans | Commercial construction
Composition of the loans
Portfolio loans, net of unearned income	307,012	341,266
Business banking
Composition of the loans
Portfolio loans, net of unearned income	1,316,346	1,303,258
Consumer loans | Consumer real estate
Composition of the loans
Portfolio loans, net of unearned income	2,028,954	1,933,509
Consumer loans | Other consumer
Composition of the loans
Portfolio loans, net of unearned income	$ 102,600	$ 104,757

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-Topic 326
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-Name Accounting Standards Codification
-Section 45
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-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Section 45
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-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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