Servicing - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Transfers And Servicing [Abstract]
Loans serviced for others unpaid principal amount	$ 380,800	$ 377,500
Capitalized service right assets included in other assets	3,600	3,300
Fair market value of the capitalized servicing rights	$ 3,200	$ 3,500
Prepayment rate	21.70%	24.10%
Discount yield	1.97%	2.38%
Valuation allowance	$ 414