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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 USD ($) Multiplier | Jan. 15, 2016 shares | Dec. 31, 2014 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |
Period for federal funds purchased and sold | 1 day |  |
Average aggregate reserve | $ 6.5 |  | $ 7.1
Loan non-accrual classification period | 90 days |  |
Days to charged consumer loans to the value of the collateral | 90 days |  |
Maximum time for re-evaluation (in months) | 12 months |  |
Re-evaluation period for real estate | 2 years |  |
Excess fair value of goodwill amount | $ 20.4 |  |
Percentage of carrying value for excess fair value | 20.30% |  |
Factor multiplication of value of goodwill | Multiplier | 5 |  |
Other real estate owned | $ 1.2 |  | $ 1.1
Percentage of likelihood of realization of recognized tax benefit, minimum | 50.00% |  |
Subsequent Event [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased | shares |  | 200,000 |
Maximum [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Maturity period of cash equivalents | 3 months |  |

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- Definition Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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