Stock Options and Employee Stock Purchase Plan - Additional Information (Detail) - USD ($)			12 Months Ended
	Mar. 06, 2014	Mar. 07, 2012	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Mar. 05, 2014
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Employee stock purchase plan aggregate number of shares (in shares)			1,602,822	1,449,409	1,240,941
Number of shares that holder entitles to purchase at specified option price			1
Duration of termination for stock plan			10 years
Unrecognized non vested stock based compensation			$ 696,000
Estimated forfeitures for unrecognized non vested stock based compensation			$ 562,000
Expected weighted average life of forfeited cost			1 year 7 months 20 days
Share-based Compensation			$ 847,000	$ 963,000
Cash received from exercises under all stock option plans			0	41,000
Tax benefits realized for tax deductions from option exercises			$ 0	$ 0
Expected shares issued			150,000
Number of complete employment days on first day of each offering period			90 days
Employee not eligible to participate			5.00%
Eligible employees contribution to purchase price			10.00%
Restricted participant under purchase plan that exceeds rate of fair value of shares			$ 25,000
Restricted participant under purchase plan that exceeds number of shares			1,000
Offering period			6 months
Purchase shares of common stock at a purchase price fair market			85.00%
Shares available to issue			23,708
Shares purchased by employees			14,708	14,067
Stock-based compensation			$ 19,000	$ 22,000
Cash received from issuance of stock under purchase plan			$ 66,000	710,000
Minimum [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Increase in number of shares under the plan			100,000
Maximum [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Increase in number of shares under the plan			150,000
Employee Stock Purchase Plan [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Cash received from issuance of stock under purchase plan			$ 66,000	$ 85,000
Qualified Employee Stock Option Plans [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Employee stock purchase plan increase in number of shares	800,000	600,000
Employee stock purchase plan aggregate number of shares (in shares)	1,800,000		366,889	586,031	853,766
Director Stock Option Plans [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Directors stock option plan increase in purchased limit		50,000
Employee stock purchase plan aggregate number of shares (in shares)			6,500	17,000	19,500
Employee Stock Purchase Plan [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Number of additional shares issued under stockholder approval						100,000
Number of shares to be granted on each meeting under directors plan						2,000