CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - 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	$ (4,796)	$ (14,376)	$ (19,005)	$ (37,584)
Other comprehensive income (loss), net of tax
Change in unrealized gains (losses) on available-for-sale securities	36	(10)	(53)	(61)
Foreign currency translation adjustments	(1,198)	452	(364)	1,499
Total other comprehensive income (loss), net of tax	(1,162)	442	(417)	1,438
Total comprehensive loss	$ (5,958)	$ (13,934)	$ (19,422)	$ (36,146)

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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