Income Taxes - Components of Income Tax Provision (Benefit) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Current income tax provision (benefit):
Federal	$ 15	$ 15	$ 16
State	70	213	1,356
Foreign	681	(1,374)	858
Total current income tax provision (benefit)	766	(1,146)	2,230
Deferred income tax (benefit):
Federal	(2,523)	(118,432)	0
State	(90)	(291)	0
Foreign	(323)	(3,413)	(276)
Total deferred income tax (benefit)	(2,936)	(122,136)	(276)
Income tax provision (benefit)	$ (2,170)	$ (123,282)	$ 1,954