Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands	Sep. 30, 2011	Sep. 30, 2010
Deferred tax assets:
Net operating loss carryforward	$ 9,373	$ 10,004
Research credit carryforward	1,388	1,028
Capital loss carryforward	21	134
Investments	1,235	1,260
Accrued compensation	1,586	2,176
Share-based compensation	24,489	23,531
Deferred revenue	1,042	2,345
Accrued lease costs	2,526	1,611
Property and equipment	4,239	5,890
Capitalized R&D		323
Other	5,988	11,356
Deferred Tax Assets, Gross, Total	51,887	59,658
Less valuation allowance	(3,422)	(3,540)
Deferred Tax Assets, Net, Total	48,465	56,118
Deferred tax liabilities:
Intangible assets	(20,541)	(19,732)
Prepaid expense	(3,942)	(4,534)
Other	(1,040)	(2,865)
Deferred Tax Liabilities	(25,523)	(27,131)
Deferred tax assets, net	$ 22,942	$ 28,987