GOODWILL AND OTHER INTANGIBLES - Summary of Changes in Carrying Value of Goodwill (Details) $ in Thousands	6 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
September 30, 2019	$ 437,067
Goodwill from acquisitions	3,125
Other adjustments including currency translations	(3,410)
March 31, 2020	436,782
Consumer and Professional Products
Goodwill [Roll Forward]
September 30, 2019	227,269
Goodwill from acquisitions	3,125
Other adjustments including currency translations	(3,410)
March 31, 2020	226,984
Home and Building Products
Goodwill [Roll Forward]
September 30, 2019	191,253
Goodwill from acquisitions	0
Other adjustments including currency translations	0
March 31, 2020	191,253
Defense Electronics
Goodwill [Roll Forward]
September 30, 2019	18,545
Goodwill from acquisitions	0
Other adjustments including currency translations	0
March 31, 2020	$ 18,545

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

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