Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (2,682)	$ 720	$ (2,704)	$ 3,526
Other comprehensive (loss) income:
Unrealized holding (losses) gains on available-for-sale securities, net of tax		(8)	(41)	42
Foreign currency translation adjustments	(2,231)	2,295	(394)	701
Other comprehensive (loss) income	(2,231)	2,287	(435)	743
Comprehensive (loss) income	$ (4,913)	$ 3,007	$ (3,139)	$ 4,269

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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