Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Deferred tax assets:
Net operating loss carryforward	$ 18,618	$ 21,529
Research credit carryforward	5,018	4,074
Accrued Bonus	8,484	3,591
Capital loss carryforward	519	165
Investments	1,059	1,101
Accrued compensation	1,381	1,662
Share-based compensation	20,238	16,443
Deferred revenue	629	2,139
Accrued lease costs	1,007	1,127
Property and equipment	2,837	2,155
Other	4,212	3,502
Deferred tax assets, gross	64,002	57,488
Less valuation allowance	(12,078)	(8,712)
Total deferred tax assets	51,924	48,776
Deferred tax liabilities:
Intangible assets	(27,391)	(29,912)
Prepaid expense	(3,966)	(3,526)
Other	(993)	(1,515)
Total deferred tax liabilities	(32,350)	(34,953)
Deferred tax assets, net	$ 19,574	$ 13,823