Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Beginning Balance			$ 195,154
Changes in unrealized losses on available-for-sale securities	$ (38)	$ 11	(89)	$ (51)
Foreign currency translation adjustments	1,039	$ 1,353	834	$ 1,047
Ending Balance	182,711		182,711
Unrealized Losses on Available-for-Sale Securities
Beginning Balance			(58)
Changes in unrealized losses on available-for-sale securities			(89)
Ending Balance	(147)		(147)
Foreign Currency Translation Adjustments
Beginning Balance			(14,172)
Foreign currency translation adjustments			834
Ending Balance	(13,338)		(13,338)
Accumulated Other Comprehensive Loss
Beginning Balance			(14,230)
Ending Balance	$ (13,485)		$ (13,485)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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