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Loans and Allowance for Credit Losses - Collateral Dependent Loans by Class of Loan (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	$ 7,981,007	$ 7,742,958
Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	25,388	2,028
Business Assets
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	3,864	9,937
Other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	5,000
Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	2,950,110	2,708,531
Commercial loans | Commercial real estate | Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	25,388	2,028
Commercial loans | Commercial real estate | Business Assets
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	0	0
Commercial loans | Commercial real estate | Other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	0
Commercial loans | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	1,275,985	1,351,637
Commercial loans | Commercial and industrial | Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	0	0
Commercial loans | Commercial and industrial | Business Assets
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	3,864	9,937
Commercial loans | Commercial and industrial | Other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	5,000
Commercial loans | Commercial construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	307,012	341,266
Commercial loans | Business banking
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	1,316,346	1,303,258
Consumer loans | Consumer real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans held for investment, outstanding balance	$ 2,028,954	$ 1,933,509

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