Loans - Additional Information (Detail)	Mar. 31, 2017 USD ($) Relationship	Dec. 31, 2016 USD ($) Relationship
Receivables [Abstract]
Outstanding amount of relationship which agreements included interest reserves	$ 3,000,000	$ 5,900,000
Number of commercial construction and land development relationship | Relationship	1	2
Amount available to fund interest payments	$ 130,000	$ 214,000
Number of relationships with interest reserves on non-accrual status | Relationship	0	0
Interest Reserve in the aggregate on non accrual status of commercial construction relationships	$ 0	$ 0