OTHER INCOME, NET (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
OTHER INCOME, NET [Abstract]
Interest income	$ 1,141	$ 659	$ 3,248	$ 1,596
Other income (expense)	486	(774)	113	(481)
Total other income (expense), net	$ 1,627	$ (115)	$ 3,361	$ 1,115

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

+ Details

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- References

No definition available.

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- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

+ References

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Data Type:	xbrli:monetaryItemType
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