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Fair Value Measurements - Balances of Assets Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | $ 91,907 | $ 94,802 | [1]
U.S. Agency and Mortgage-Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 77,227 | 80,171 |
Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 14,669 | 14,620 |
Corporate Equity Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 11 | 11 |
Fair Value, Measurements, Recurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 91,907 | 94,802 |
Fair Value, Measurements, Recurring [Member] | U.S. Agency and Mortgage-Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 77,227 | 80,171 |
Fair Value, Measurements, Recurring [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 14,669 | 14,620 |
Fair Value, Measurements, Recurring [Member] | Corporate Equity Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 11 | 11 |
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 11 | 11 |
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate Equity Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 11 | 11 |
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 91,896 | 94,791 |
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Agency and Mortgage-Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | 77,227 | 80,171 |
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Available for sale Securities, Fair Value | $ 14,669 | $ 14,620 |
[1] | Derived from audited consolidated financial statements.

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