Quarterly Financial Data (Details) (USD $)	3 Months Ended																12 Months Ended
	Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 51,612,000		$ 47,885,000		$ 45,882,000		$ 47,322,000		$ 51,369,000		$ 48,824,000		$ 48,197,000		$ 46,991,000		$ 192,701,000	$ 195,381,000	$ 190,558,000
Gross profit	23,647,000		22,149,000		21,780,000		22,908,000		25,963,000		24,720,000		24,961,000		24,479,000		90,484,000	100,123,000	100,337,000
Net income (loss)	426,000	[1]	(101,000)	[1]	738,000	[1]	688,000	[1]	2,047,000	[1],[2],[3],[4]	1,528,000	[1],[2],[3],[4]	1,000,000	[1],[2],[3],[4]	1,230,000	[1],[2],[3],[4]	1,751,000	5,805,000	7,615,000
Net income per common share, basic (USD per share)	$ 0.02		$ 0.00		$ 0.03		$ 0.03		$ 0.08		$ 0.06		$ 0.04		$ 0.05		$ 0.07	$ 0.22	$ 0.30
Net income per common share, diluted (USD per share)	$ 0.02		$ 0.00		$ 0.03		$ 0.03		$ 0.08		$ 0.06		$ 0.04		$ 0.05		$ 0.07	$ 0.22	$ 0.29
Net tax benefits
Net tax benefits			100,000		1,100,000		200,000		200,000		100,000		400,000		100,000		1,400,000	800,000
Restructuring Charges [Abstract]
Restructuring charge									350,000								152,000	350,000	963,000
Restructuring accrual, net of tax									227,000
Litigation Settlement [Abstract]
Litigation Settlement (charge)													(1,500,000)
Litigation settlement amount (charge), net of tax													(1,000,000)
Impairment of Intangible Assets (Excluding Goodwill) [Abstract]
Intangible impairment charge									361,000								0	361,000	0
Intangible impairment charge, net of taxes									$ 200,000

[1] During fiscal 2014 and 2013, we recorded net tax benefits of $1.4 million and $0.8 million, respectively. We recorded a benefit of $0.2 million in the first quarter of fiscal 2014 resulting from the release of income tax reserves due to the expiration of the statute of limitations from various U.S. and foreign tax jurisdictions. During the second quarter of fiscal 2014, we recorded a tax benefit of $1.1 million resulting from re-measurement and reversal of certain income tax reserves as a result of a federal income tax audit for fiscal 2012. In the third quarter of fiscal 2014, we recorded a tax benefit of $0.1 million primarily for a valuation allowance reversal associated with the reassessment of state research and development tax credits. We recorded net tax benefits of $0.1 million in the first quarter of fiscal 2013 resulting from the release of income tax reserves due to the expiration of the statute of limitations from various U.S. and foreign tax jurisdictions. During the second quarter of fiscal 2013, we recorded a tax benefit of $0.4 million resulting from the enactment of legislation on January 2, 2013 extending the research and development credit for the last three quarters of fiscal 2012. In the third quarter of fiscal 2013, we recorded a tax benefit of $0.1 million for the release of income tax reserves due to the expiration of the statute of limitations for U.S. Federal income tax for fiscal 2009. In the fourth quarter of fiscal 2013, we recorded a tax benefit of $0.2 million for the reversal of tax reserves resulting from expiration of the statute of limitations for state income taxes.

[2] During fiscal 2013, we recorded a business restructuring accrual of $0.4 million ($0.2 million after tax) in the fourth quarter of fiscal 2013.

[3] During the second quarter of fiscal 2013, we recorded a charge of $1.5 million ($1.0 million after tax) for the settlement of a patent infringement lawsuit.

[4] During the fourth quarter of fiscal 2013, we recorded a charge of $0.4 million ($0.2 million after tax) for impairment of certain intangibles.