Loans - Summary of Portfolio Loans by Category (Details) - Portfolio loans, net - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	$ 6,164,492	$ 5,316,953
Unearned loan fees, net	(24,441)	(2,616)
Loans, including unearned loan fees	6,140,051	5,314,337
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	3,165,611	2,361,157
Loans, including unearned loan fees	3,143,197
Commercial - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	1,309,895	1,299,884
Loans, including unearned loan fees	1,309,895
Commercial - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	738,549	697,437
Loans, including unearned loan fees	738,549
Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	481,221	457,273
Loans, including unearned loan fees	481,221
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	326,992	366,261
Loans, including unearned loan fees	326,992
Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,856,657	2,820,855
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	142,224	$ 134,941
Loans, including unearned loan fees	$ 140,197

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Amount, after fee received for commitment to originate or purchase, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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