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Fair Value Measurements - Balances of Assets Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available for sale Securities, Fair Value | $ 112,468 | $ 83,292
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 | 96,220 | 67,029
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 | 16,241 | 16,257
Corporate Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available for sale Securities, Fair Value | 7 | 6
Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available for sale Securities, Fair Value | 112,468 | 83,292
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 | 96,220 | 67,029
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 | 16,241 | 16,257
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 | 7 | 6
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 | 7 | 6
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 | 7 | 6
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 | 112,461 | 83,286
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 | 96,220 | 67,029
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 | $ 16,241 | $ 16,257

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