Marketable Securities (Amortized Cost And Approximate Fair Values Of Marketable Securities) (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
Schedule of Investments [Line Items]
Adjusted Cost	$ 89,840,725	$ 93,003,640
Gross Unrealized Gains	1,188,741	1,630,343
Gross Unrealized Losses	(16,371)	(251,582)
Fair Market Value	91,013,095us-gaap_AvailableForSaleSecurities	94,382,401us-gaap_AvailableForSaleSecurities
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Adjusted Cost	88,456,886	88,567,210
Gross Unrealized Gains	1,185,469	1,613,822
Gross Unrealized Losses	(16,371)	(246,973)
Fair Market Value	89,625,984	89,934,059
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Adjusted Cost	1,383,839	4,436,430
Gross Unrealized Gains	3,272	16,521
Gross Unrealized Losses		(4,609)
Fair Market Value	$ 1,387,111	$ 4,448,342

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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