Acquisition of MainStreet - Changes in Fair Value of Assets and Liabilities Acquired (Details) $ in Thousands	3 Months Ended
Sep. 30, 2015 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 44,333
MainStreet BankShares, Inc.
Business Acquisition [Line Items]
Goodwill	5,167
Goodwill	5,290
MainStreet BankShares, Inc. \| Loans Receivable [Member]
Business Acquisition [Line Items]
Effect of adjustments to goodwill	(353)
MainStreet BankShares, Inc. \| Property, Plant and Equipment [Member]
Business Acquisition [Line Items]
Effect of adjustments to goodwill	289
MainStreet BankShares, Inc. \| Other Assets [Member]
Business Acquisition [Line Items]
Effect of adjustments to goodwill	$ 187

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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+ References

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