Investments - Summary of Investments by Type of Security (Detail) - USD ($)	Sep. 30, 2015	Sep. 30, 2014
Schedule Of Available For Sale Securities [Line Items]
Cost	$ 23,924,252	$ 18,348,998
Gross Unrealized Gains	3,466	1,472
Gross Unrealized Losses	(6,390)	(9,282)
Fair Market Value	23,921,328	18,341,188
Corporate debt securities [Member] \| Short-term [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost	23,924,252	16,273,996
Gross Unrealized Gains	3,466	1,472
Gross Unrealized Losses	(6,390)	(6,298)
Fair Market Value	$ 23,921,328	16,269,170
Corporate debt securities [Member] \| Long-term [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost		2,075,002
Gross Unrealized Losses		(2,984)
Fair Market Value		$ 2,072,018

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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