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Acquisition - Additional Information (Detail) |  | 12 Months Ended
--- | --- | ---
Apr. 17, 2015 USD ($) Branches | Dec. 31, 2015 Branch
Business Acquisition [Line Items] |  |
Cash paid for deposits, premises and equipment | $ 6,618,000 |
Amount for acquisition of premises and equipment | 4,495,000 |
Total deposits liabilities assumed | 186,819,000 |
Bank of America [Member] |  |
Business Acquisition [Line Items] |  |
Number of acquired branches | Branch |  | 6
Amount for acquisition of premises and equipment | 2,165,000 |
Total deposits liabilities assumed | 186,136,000 |
Loans acquired | $ 0 |
Bank of America [Member] | Virginia [Member] |  |
Business Acquisition [Line Items] |  |
Number of acquired branches | Branches | 6 |

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- Definition Amount of liabilities assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 + Details
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