Fair Value Measurements - Financial Assets and Financial Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available for sale	$ 30,108	$ 19,804
Items Measured on a Recurring Basis [Member] | U.S. Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available for sale	30,108	19,804
Items Measured on a Non-Recurring Basis [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value	3,262	4,664
Items Measured on a Non-Recurring Basis [Member] | Loans Measured for Impairment Based on the Fair Value of Underlying Collateral [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value	12,844	11,675
Level 2 Inputs [Member] | Items Measured on a Recurring Basis [Member] | U.S. Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available for sale	30,108	19,804
Level 3 Inputs [Member] | Items Measured on a Non-Recurring Basis [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value	3,262	4,664
Level 3 Inputs [Member] | Items Measured on a Non-Recurring Basis [Member] | Loans Measured for Impairment Based on the Fair Value of Underlying Collateral [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value	$ 12,844	$ 11,675