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Fair Value of Instruments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013 | Mar. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Interest-bearing deposits maturing date | 90 days |  |
Carrying amounts of dividends payable, number of days | Forty days |  |
Impaired loans categorized as Level 3 | $ 2,059 | $ 2,440 | $ 4,144
Specific allocation for impaired loans | 261 | 516 | 860
Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Impaired loans categorized as Level 3 | 1,800 | 1,900 |
Fair Value on a Recurring Basis [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Specific allocation for impaired loans | $ 261 | $ 516 |

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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524 + Details
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