Note 6 - Stock-Based Compensation (Detail) - Stock Option Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
	Jun. 30, 2012
Outstanding at October 1, 2011 (in Shares)	994
Outstanding at June 30, 2012 (in Shares)	1,058
Outstanding at June 30, 2012	6 years 208 days
Outstanding at June 30, 2012 (in Dollars)	$ 1,372
Vested and anticipated to vest in the future at June 30, 2012 (in Shares)	1,037
Vested and anticipated to vest in the future at June 30, 2012	6 years 193 days
Vested and anticipated to vest in the future at June 30, 2012 (in Dollars)	1,357
Exercisable at June 30, 2012 (in Shares)	713
Exercisable at June 30, 2012	5 years 197 days
Exercisable at June 30, 2012 (in Dollars)	1,140
Granted (in Shares)	76
Exercised (in Shares)	(12)
Exercised (in Dollars)	$ 147
Minimum [Member]
Outstanding at October 1, 2011	$ 0.18
Outstanding at June 30, 2012	$ 0.36
Granted	$ 13.06
Exercised	$ 0.18
Maximum [Member]
Outstanding at October 1, 2011	$ 20.27
Outstanding at June 30, 2012	$ 20.27
Granted	$ 13.06
Exercised	$ 0.18
Weighted Average [Member]
Outstanding at October 1, 2011	$ 10.89
Outstanding at June 30, 2012	$ 11.17
Vested and anticipated to vest in the future at June 30, 2012	$ 11.17
Exercisable at June 30, 2012	$ 11.19
Granted	$ 13.06
Exercised	$ 0.18