Securities - Summary of Amortized Cost and Estimated Fair Values of Securities Held for Investment (Detail) - USD ($) $ in Thousands |
Mar. 31, 2016 |
Dec. 31, 2015 |
---|---|---|
Schedule of Held-to-maturity Securities [Line Items] | ||
Amortized Cost | $ 8,379 | $ 8,789 |
Gross Unrealized Gains | 55 | 61 |
Estimated Fair Value | 8,434 | 8,850 |
Mortgage Backed Securities [Member] | ||
Schedule of Held-to-maturity Securities [Line Items] | ||
Amortized Cost | 323 | 347 |
Gross Unrealized Gains | 25 | 25 |
Estimated Fair Value | 348 | 372 |
States and Political Subdivisions [Member] | ||
Schedule of Held-to-maturity Securities [Line Items] | ||
Amortized Cost | 7,556 | 7,942 |
Gross Unrealized Gains | 30 | 36 |
Estimated Fair Value | 7,586 | 7,978 |
Other Securities [Member] | ||
Schedule of Held-to-maturity Securities [Line Items] | ||
Amortized Cost | 500 | 500 |
Estimated Fair Value | $ 500 | $ 500 |