Loans - Summary of Portfolio Loans by Category (Details) - Portfolio loans, net - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	$ 7,241,500	$ 7,241,074
Unearned loan fees, net	(15,233)	(16,139)
Loans, including unearned loan fees	7,226,267	7,224,935
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,943,048	3,100,299
Loans, including unearned loan fees	2,930,805	3,088,995
Commercial - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	1,646,021	1,589,419
Loans, including unearned loan fees	1,646,021	1,589,419
Commercial - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	1,554,727	1,498,408
Loans, including unearned loan fees	1,554,727	1,498,408
Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	556,776	546,686
Loans, including unearned loan fees	556,776	546,686
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	305,497	319,179
Loans, including unearned loan fees	305,497	319,179
Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	4,063,021	3,953,692
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	235,431	187,083
Loans, including unearned loan fees	$ 232,441	$ 182,248

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

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