Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 1,262	$ 1,534	$ 2,572	$ (22)
Other comprehensive (loss) income:
Unrealized holding gains (losses) on available-for-sale securities, net of tax	39	(28)	44	(41)
Foreign currency translation adjustments	(779)	1,207	(1,318)	1,837
Other comprehensive (loss) income	(740)	1,179	(1,274)	1,796
Comprehensive income	$ 522	$ 2,713	$ 1,298	$ 1,774

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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