Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (146)	$ (19,212)
Other comprehensive income (loss):
Change in unrealized losses on available-for-sale securities, net of tax	82	(24)
Foreign currency translation adjustments	(220)	(1,365)
Other comprehensive loss	(138)	(1,389)
Total comprehensive loss	$ (284)	$ (20,601)

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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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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