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Fair Values - Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis (Detail) (Fair Value, Measurements, Nonrecurring [Member], USD $) | Sep. 30, 2013 | Dec. 31, 2012
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | $ 31,205,000 | $ 34,406,000
Foreclosed assets | 3,549,000 | 6,970,000
Total | 34,754,000 | 41,376,000
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 0 | 0
Foreclosed assets | 0 | 0
Total | 0 | 0
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 0 | 0
Foreclosed assets | 0 | 0
Total | 0 | 0
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 31,205,000 | 34,406,000
Foreclosed assets | 3,549,000 | 6,970,000
Total | $ 34,754,000 | $ 41,376,000

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- Details
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