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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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Investments In Securities (Schedule Of Gross Realized Gains And Losses On Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			$ 484	$ 298
Total, Gross realized losses			(47)	(125)
Net realized gain from securities			437	173
Gain on other investments			4	13
Total			4	13
Net realized investment gains	$ 288	$ 83	441	186
Issuer Obligations Of U S States Territories And Political Subdivisions Special Revenue [Member]
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			0	0
Total, Gross realized losses			0	0
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			0	0
Common Stocks And Nonredeemable Preferred Stocks
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			484	298
Total, Gross realized losses			(47)	(125)
General Obligations Of U.S. States, Territories And Political Subdivisions
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized losses			0	0
Impairments of Debt And Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized losses			$ 0	$ 0