Annual report pursuant to Section 13 and 15(d)

Premises and Equipment - Additional Information (Detail)

v3.20.4
Premises and Equipment - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property Plant And Equipment [Abstract]      
Depreciation and amortization expense $ 4.0 $ 3.3 $ 2.6