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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 ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			$ 1,232,469	$ 955,824
Total, Gross realized losses			(255,581)	(404,247)
Net realized gain from securities			976,888	551,577
Gain on other investments			13,230	22,751
Total			13,230	22,751
Net realized gain on investments	$ 803,938	$ 439,326	990,118	574,328
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			139	161
Total, Gross realized losses			(100)	(1,085)
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			0	20
Common Stocks And Nonredeemable Preferred Stocks
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			1,232,330	880,647
Total, Gross realized losses			(255,481)	(168,688)
Auction Rate Securities
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized gains			0	74,996
General Obligations Of U.S. States, Territories And Political Subdivisions
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized losses			0	(533)
Impairments of Debt And Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total, Gross realized losses			$ 0	$ (233,941)