Income Taxes - Schedule of Deferred Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Depreciable assets	$ 1,271	$ 1,146
Deferred revenue	74	85
Accruals and reserves	353	362
Stock-based compensation	4,220	3,883
Impaired strategic investments	3,253	6,455
Unrealized gains on investments	(29)	(131)
Capital loss carry forward	1,962
Other	733	755
Valuation allowance	(5,293)	(6,530)
Total deferred tax assets	6,544	6,025
Less current deferred tax assets	(506)	(219)
Noncurrent deferred tax assets	$ 6,038	$ 5,806