Other Than Temporary Impairment Credit Losses Recognized In Earnings

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- Definition

Percent Of Average Daily Trading Volume

+ References

No definition available.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5086-111524

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284393-111563

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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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Investments (Narrative) (Details) - USD ($)	9 Months Ended		12 Months Ended
Investments (Narrative) (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Investments [Line Items]
Credit-related net investment impairment losses	$ 400,000.0	$ 0	$ 0
Credit-related investment impairment losses recognized in earnings	$ 10,500,000
Percent of average daily trading volume	0.20%		0.20%
Carrying value of securities pledged	$ 285,000,000		$ 273,000,000
Debt Securities [Member]
Schedule of Investments [Line Items]
Credit-related investment impairment losses recognized in earnings	8,900,000
Equity Securities [Member]
Schedule of Investments [Line Items]
Credit-related investment impairment losses recognized in earnings	$ 1,600,000
Maximum [Member] \| First National Corporation (FXNC) [Member]
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	4.00%		4.00%
Maximum [Member] \| Eagle Financial Services, Inc. (EFSI) [Member]
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	1.50%		1.50%