Income Taxes - Deferred Tax Assets and Liabilities (Detail) (USD $)	Sep. 30, 2013	Sep. 30, 2012
Deferred Tax Assets:
Accrued liabilities and reserves	$ 338,000	$ 823,000
Allowance for doubtful accounts	115,000	137,000
Inventory	202,000	162,000
R&D tax credits carry-forwards	805,000
Non-deductible stock compensation	178,000	87,000
Net operating losses carry-forwards	59,000
Other	57,000	11,000
Gross Deferred Tax Assets	1,754,000	1,220,000
Deferred and Other Tax Liabilities:
Unrealized gain on investments	(736,000)	(310,000)
Percentage of completion		(566,000)
Property, plant and equipment	(1,179,000)	(1,006,000)
Unrecognized tax benefits	(300,000)	(300,000)
Other	(23,000)	(12,000)
Gross Deferred and Other Tax Liabilities	(2,238,000)	(2,194,000)
Net Deferred Income and Other Tax Liabilities	$ (484,000)	$ (974,000)