Business Combination - Additional Information (Detail) - Subsequent Event - Virginia BanCorp $ in Millions	Apr. 01, 2017 USD ($) shares
Business Acquisition [Line Items]
Ownership percentage by shareholders of acquiring entity	51.00%
Ownership percentage by shareholders of acquired entity	49.00%
Common stock exchange ratio	1.178
Business combination, number of shares exchanged \| shares	4,586,221
Business combination, value of shares exchanged \| $	$ 40.5

Common Stock Exchange Ratio

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- Definition

Percentage of ownership by acquired company's shareholders in the combined company.

+ References

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- Definition

Percentage of ownership by acquiring company's shareholders in the combined company.

+ References

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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