Loans - Summary of Portfolio Loans by Category (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	$ 9,354,987	$ 9,017,642
Portfolio loans, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	9,361,916	9,026,780
Unearned loan fees, net	(6,929)	(9,138)
Loans, including unearned loan fees	9,354,987	9,017,642
Portfolio loans, net \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	3,710,012	3,396,590
Loans, including unearned loan fees	3,709,893	3,392,375
Portfolio loans, net \| Commercial - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,286,458	2,141,143
Loans, including unearned loan fees	2,286,458	2,141,143
Portfolio loans, net \| Commercial - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,152,189	2,035,785
Loans, including unearned loan fees	2,152,189	2,035,785
Portfolio loans, net \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	583,649	734,073
Loans, including unearned loan fees	583,649	734,073
Portfolio loans, net \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	397,450	454,052
Loans, including unearned loan fees	397,450	454,052
Portfolio loans, net \| Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	5,419,746	5,365,053
Portfolio loans, net \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	232,158	265,137
Loans, including unearned loan fees	$ 225,348	$ 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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