Other Assets - Summary of Changes in Net Amount of Capitalized Implementation Costs for Software Hosting Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Capitalized Computer Software Net [Abstract]
Balance, beginning of period	$ 943	$ 1,188	$ 1,181	$ 1,166
Capitalized implementation fees	32	7	130	87
Amortization of implementation fees	(172)	(65)	(508)	(123)
Balance, end of period	$ 803	$ 1,130	$ 803	$ 1,130