nongovernmentalissuerover10%ofequity

No definition available.

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- Definition

Other That Temporary Impairment Credit Losses Recognized In Earnings

+ 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

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&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://fasb.org/us-gaap/role/ref/legacyRef
-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.

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Investments (Narrative) (Details) - USD ($)	12 Months Ended
Investments (Narrative) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Investments [Line Items]
Credit-related net investment impairment losses	$ 0	$ 0	$ 500,000
Other that temporary impairment credit losses recognized in earnings	1,600,000
nongovernmentalissuerover10%ofequity	$ 0	0
Maximum
Schedule of Investments [Line Items]
Regional community bank stocks, percent of average trading volumes	0.20%
First National Corporation (FXNC) [Domain] \| Maximum
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	4.00%
Eagle Financial Services, Inc. (EFSI) [Domain] \| Maximum
Schedule of Investments [Line Items]
Equity ownership positions in the community bank holding companies	1.50%
Asset Pledged as Collateral [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Restricted	$ 510,000,000	$ 429,000,000