Foreclosed Assets - Presentation of Balances in Foreclosed Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned	$ 4,975	$ 2,397	$ 741	$ 1,736
Multi-Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned	750	1,775	141
One-to-Four Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned	1,025	135		55
Home Equity Line of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned		28	68
Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned	$ 3,200		73	943
Non-Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total other assets owned		$ 459	$ 459	$ 738