WARRANTY LIABILITY (Details) - Summary of Changes in Warrant Liability Included in Accrued Liabilities - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance, beginning of period	$ 6,258	$ 5,803	$ 6,236	$ 6,322
Warranties issued and changes in estimated pre-existing warranties	2,777	803	5,889	3,310
Actual warranty costs incurred	(1,450)	(1,457)	(5,376)	(4,483)
Other warranty liabilities assumed from acquisitions	0	0	836	0
Balance, end of period	$ 7,585	$ 5,149	$ 7,585	$ 5,149

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of increase (decrease) in the standard and extended product warranty liability.

+ References

+ Details

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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

+ Details

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- Definition

Amount of increase in the standard product warranty accrual from a business acquisition. Excludes extended product warranties.

+ References

+ Details

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