Loans - Summary of Portfolio Loans by Category (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	$ 9,056,073	$ 9,017,642
Portfolio loans, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	9,064,414	9,026,780
Unearned loan fees, net	(8,341)	(9,138)
Financing Receivable, Covered, after Allowance for Credit Loss, Total	9,056,073	9,017,642
Portfolio loans, net \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	3,400,574	3,396,590
Financing Receivable, Covered, after Allowance for Credit Loss, Total	3,398,723	3,392,375
Portfolio loans, net \| Commercial - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,184,126	2,141,143
Financing Receivable, Covered, after Allowance for Credit Loss, Total	2,184,126	2,141,143
Portfolio loans, net \| Commercial - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,094,012	2,035,785
Financing Receivable, Covered, after Allowance for Credit Loss, Total	2,094,012	2,035,785
Portfolio loans, net \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	702,630	734,073
Financing Receivable, Covered, after Allowance for Credit Loss, Total	702,630	734,073
Portfolio loans, net \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	432,639	454,052
Financing Receivable, Covered, after Allowance for Credit Loss, Total	432,639	454,052
Portfolio loans, net \| Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	5,413,407	5,365,053
Portfolio loans, net \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	250,433	265,137
Financing Receivable, Covered, after Allowance for Credit Loss, Total	$ 243,943	$ 260,214

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Amount, after allowance, of finance receivable covered by loss sharing agreement.

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Amount, before allowance for credit loss, of financing receivable.

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