Loans - Summary of Changes in Loans to Directors, Executive Officers and Affiliates (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Balance at beginning of the year	$ 32	$ 57
Repayments	$ (32)	(25)
Balance at end of year		$ 32