Loans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Mar. 01, 2019
Loans [Line Items]
Nonaccruing loans	$ 22,900	$ 30,100
Potential increase in net interest income	1,200	2,000
Accrued interest receivable	38,094	22,001
Loans acquired	400	227
Accrued interest receivable	38,094	22,001
Beneficial
Loans [Line Items]
Loans acquired			$ 37,000
Loans Receivable
Loans [Line Items]
Accrued interest receivable	31,500	17,000
Accrued interest receivable	31,500	17,000
First Mortgage
Loans [Line Items]
Amounts of loans serviced	272,000	98,600
Fees from servicing of loans	1,200	500
Value of servicing rights	1,200	300
First Mortgage | Servicing Rights
Loans [Line Items]
Net losses	700	200
SBA Loans
Loans [Line Items]
Value of servicing rights	$ 2,100	$ 1,100