XML 24 R104.htm IDEA: XBRL DOCUMENT v2.4.1.9

Rights Offering of Common Stock - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Sale of common shares under rights offering	1,945,815fxnc_StockIssuedDuringPeriodSharesRightsExercised
Rights exercised by existing shareholders	1,520,815fxnc_NumberOfRightsToPurchaseCommonStockExercisedDuringPeriod
Subscription price of share	$ 4.00us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Rights purchased by standby investors	425,000fxnc_NumberOfAdditionalRightsToPurchaseCommonStockExercisedDuringPeriod
Proceeds from rights issued, net of offering costs	$ 7.6fxnc_ProceedsFromSaleOfCommonStockInRightsOffering

X

- Definition

Number of additional rights to purchase common stock exercised during period.

+ References

No definition available.

+ Details

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Namespace Prefix:	fxnc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of rights to purchase common stock exercised during period.

+ References

No definition available.

+ Details

Name:	fxnc_NumberOfRightsToPurchaseCommonStockExercisedDuringPeriod
Namespace Prefix:	fxnc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Proceeds from sale of common stock in rights offering.

+ References

No definition available.

+ Details

Name:	fxnc_ProceedsFromSaleOfCommonStockInRightsOffering
Namespace Prefix:	fxnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Stock issued during period shares rights exercised.

+ References

No definition available.

+ Details

Name:	fxnc_StockIssuedDuringPeriodSharesRightsExercised
Namespace Prefix:	fxnc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Details

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Period Type:	duration