Loans and Allowance for Loan Losses - Summary of Loans Held for Investment (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 2,316,726	$ 1,025,687
Less: Deferred loan fees, net of costs	(12,184)	(4,271)
Total	2,304,542	1,021,416
Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	286,835	123,675
Paycheck Protection Program [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	608,692	292,068
Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	155,631	54,702
Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	49,338	18,040
Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	649,474	273,499
Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	496,301	213,404
Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	5,245	3,615
Consumer [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 65,210	$ 46,684

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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