Acquisition of MainStreet - Acquired Loans (Details) - MainStreet BankShares, Inc. $ in Thousands	Jan. 01, 2015 USD ($)
Business Acquisition [Line Items]
Contractually required principal and interest at acquisition	$ 33,066
Contractual cash flows not expected to be collected (nonaccretable difference)	1,828
Expected cash flows at acquisition	34,894
Interest component of expected cash flows (accretable yield)	7,647
Fair value of acquired loans accounted for under FASB ASC 310-30	$ 27,247

Refers to the amount which is contractual cash flows not expected to be collected (non accretable difference).

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Refers to the amount as interest component of expected cash flows (accretable discount).

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- Definition

Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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-Name Accounting Standards Codification

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-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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-Name Accounting Standards Codification

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-Section 15

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-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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Amount of contractually required payments receivable at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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