Loans - Schedule of Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Receivables [Abstract]
Impaired loans without a valuation allowance	$ 5,835	$ 1,228	$ 2,461	$ 5,835	$ 2,461	$ 1,228
Impaired loans with a valuation allowance	4,918	10,711	9,388	4,918	9,388	10,711
Total impaired loans	10,753	11,939	11,849	10,753	11,849	11,939
Valuation allowance related to impaired loans	2,436	2,184	2,400	2,436	2,400	2,184
Total non-accrual loans	5,470	8,076	6,248	5,470	6,248	8,076
Total loans past-due ninety days or more and still accruing	0	0	0	0	0	0
Average investment in impaired loans	$ 10,662	$ 11,676	$ 11,639	$ 11,059	$ 12,360	$ 12,247