Marketable Securities (Amortized Cost And Approximate Fair Values Of Marketable Securities) (Details) (USD $)	Dec. 31, 2013	Mar. 31, 2013
Schedule of Investments [Line Items]
Adjusted Cost	$ 89,628,926	$ 80,304,725
Gross Unrealized Gains	1,746,731	2,459,903
Gross Unrealized Losses	(497,711)	(13,342)
Fair Market Value	90,877,946	82,751,286
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Adjusted Cost	84,677,016	72,923,502
Gross Unrealized Gains	1,716,210	2,378,845
Gross Unrealized Losses	(493,700)	(4,187)
Fair Market Value	85,899,526	75,298,160
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Adjusted Cost	4,951,910	7,381,223
Gross Unrealized Gains	30,521	81,058
Gross Unrealized Losses	(4,011)	(9,155)
Fair Market Value	$ 4,978,420	$ 7,453,126