Accumulated Other Comprehensive Income Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Beginning Balance	$ 195,154	$ 244,467	$ 289,624
Other comprehensive income (loss)	(1,389)	1,711	(2,996)
Ending Balance	176,587	195,154	244,467
Unrealized Gains (Losses) on Available-for-Sale Securities
Beginning Balance	(58)	(15)	(3)
Other comprehensive income (loss)	(24)	(43)	(12)
Ending Balance	(82)	(58)	(15)
Foreign Currency Translation Adjustments
Beginning Balance	(14,172)	(15,926)	(12,942)
Other comprehensive income (loss)	(1,365)	1,754	(2,984)
Ending Balance	(15,537)	(14,172)	(15,926)
Accumulated Other Comprehensive Loss
Beginning Balance	(14,230)	(15,941)	(12,945)
Other comprehensive income (loss)	(1,389)	1,711	(2,996)
Ending Balance	$ (15,619)	$ (14,230)	$ (15,941)

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(31))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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