Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (4,457)	$ 3,926	$ 9,985
Other comprehensive (loss) income:
Unrealized holding (losses) gains on available-for-sale securities, net of tax	(38)	49	(68)
Foreign currency translation adjustments	(661)	2,095	1,336
Other comprehensive (loss) income	(699)	2,144	1,268
Comprehensive (loss) income	$ (5,156)	$ 6,070	$ 11,253

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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