Loans and Allowance for Loan Losses - Summary of Nonperforming and Restructured Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summary Of Nonperforming And Restructured Assets [Abstract]
Past due 90 days or more and still accruing	$ 11,834	$ 1,916
Nonaccrual	17,965	22,603
Restructured	18,010	13,188
Total nonperforming and restructured loans	47,809	37,707
Other real estate owned and repossessed assets	6,073	6,873
Total nonperforming and restructured assets	$ 53,882	$ 44,580