Disclosures about Fair Value of Assets and Liabilities - Fair Value Measurements of Assets on a Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	$ 45,961	$ 48,084
Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	45,961	48,084
Ginnie Mae and GSE Mortgage-Backed Pass-Through Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	42,238	44,198
Ginnie Mae and GSE Mortgage-Backed Pass-Through Securities [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	42,238	44,198
Ginnie Mae Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,816	2,019
Ginnie Mae Collateralized Mortgage Obligations [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,816	2,019
Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,907	1,867
Mutual Fund [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,907	1,867
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,907	1,867
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mutual Fund [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	1,907	1,867
Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	44,054	46,217
Significant Other Observable Inputs (Level 2) [Member] | Ginnie Mae and GSE Mortgage-Backed Pass-Through Securities [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	42,238	44,198
Significant Other Observable Inputs (Level 2) [Member] | Ginnie Mae Collateralized Mortgage Obligations [Member] | Fair Value Measured on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value	$ 1,816	$ 2,019