Equity Securities, FV-NI, Unrealized Gain (Loss)

No definition available.

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- Definition

The cumulative amount of credit losses recognized in earnings related to investments held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

No definition available.

+ Details

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- Definition

Percent Of Average Daily Trading Volume

+ References

No definition available.

+ Details

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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=84173941&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

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

+ References

No definition available.

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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=82897076&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

No definition available.

+ Details

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Investments (Narrative) (Details) - USD ($)	3 Months Ended
Investments (Narrative) (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Investments [Line Items]
Credit-related net investment impairment losses	$ 0	$ 0
Credit-related investment impairment losses recognized in earnings	$ 1,800,000
Percent of average daily trading volume	0.40%		0.40%
Equity and perpetual preferred security unrealized gains recognized	$ 180,000
Reclassification from AOCI to retained earnings	0
Net gains on sale of investment securities	0	$ 4,276,000
Carrying value of securities pledged	448,000,000		$ 429,000,000
Debt Securities
Schedule of Investments [Line Items]
Credit-related investment impairment losses recognized in earnings	200,000
Equity Securities
Schedule of Investments [Line Items]
Credit-related investment impairment losses recognized in earnings	$ 1,600,000
Maximum \| First National Corporation (FXNC)
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	4.00%		4.00%
Maximum \| Eagle Financial Services, Inc. (EFSI)
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	1.50%		1.50%
Accounting Standards Update 2016-01 \| Accumulated Other Comprehensive Income (Loss)
Schedule of Investments [Line Items]
Reclassification from AOCI to retained earnings	$ 2,657,000