Loans and Allowance for Credit Losses - Summary of Amortized Cost Basis of Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	$ 38,321	$ 36,054
Nonaccrual With No ACL	15,429	28,085
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	12,235	7,501
Nonaccrual With No ACL	4,700	6,623
Construction, land development, land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	2,089	3,922
Nonaccrual With No ACL	1,180	2,987
1-4 family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	1,761	1,730
Nonaccrual With No ACL	1,640	1,694
Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	2,452	6,494
Nonaccrual With No ACL	2,452	6,494
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	19,462	16,080
Nonaccrual With No ACL	5,210	9,977
Factored receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	0	0
Nonaccrual With No ACL	0	0
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	322	327
Nonaccrual With No ACL	247	310
Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	0	0
Nonaccrual With No ACL	$ 0	$ 0