Quarterly Financial Data (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2012	Sep. 30, 2011
Quarterly financial information
Revenue	$ 6,219	$ 7,757	$ 5,928	$ 6,185	$ 6,677	$ 7,090	$ 5,525	$ 5,930	$ 26,090	$ 25,222
Gross margin	4,497	5,555	4,284	4,507	4,852	4,928	3,870	4,261	18,844	17,911
Income (loss) from operations	(186)	399	(32)	(72)	(277)	361	(152)	346	109	278
Net income (loss)	$ (103)	$ 559	$ (115)	$ (184)	$ (406)	$ 212	$ (272)	$ 223	$ 157	$ (243)
Basic and diluted net income (loss) per share	$ (0.03)	$ 0.14	$ (0.03)	$ (0.05)	$ (0.11)	$ 0.06	$ (0.07)	$ 0.06