Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Common stock equivalents included in Diluted earnings per share				0
Weighted-average shares issuable upon the exercise of stock options, included in Diluted EPS			84,000
Common Stock Equivalents			2,000
Cash equivalents consist of short-term certificates of deposit maturities period			3 months
Net unrealized gains			$ 1,141,000	$ 4,596,000
Estimated interest accrued			399,000	545,000
Transfers of investments between Level 1 and Level 2	0	0	0	0
Impairment loss on property, equipments and intangible assets			0	0
Time for the collection of cost associated with Pre- contract			1 year
Valuation allowance	0	0	0	0
Three to Four Years Old Inventory [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Cost basis reduction in inventory, percentage			50.00%
Three to Four Years Old Inventory [Member] | Minimum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory, time period on the shelf, years			3 years
Three to Four Years Old Inventory [Member] | Maximum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory, time period on the shelf, years			4 years
Four to Five Years Old Inventory [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Cost basis reduction in inventory, percentage			75.00%
Four to Five Years Old Inventory [Member] | Minimum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory, time period on the shelf, years			4 years
Four to Five Years Old Inventory [Member] | Maximum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory, time period on the shelf, years			5 years
Greater Than Five Years Old Inventory [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory valuation estimate			$ 0
Greater Than Five Years Old Inventory [Member] | Minimum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Inventory, time period on the shelf, years			5 years
Stock Option [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Weighted-average shares issuable upon the exercise of stock options, not included in Diluted EPS			261,000	327,000
United States [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Percentage of net revenue from one or more separate U.S corporate entities on quarterly basis	4.00%	21.00%
Percentage of net revenue from one or more separate U.S corporate entities on yearly basis			11.00%	26.00%