BUSINESS SEGMENTS - Segment EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 55,160	$ 45,381
Net interest expense	(15,950)	(16,331)
Depreciation and amortization	(15,825)	(15,085)
Income before taxes	16,951	13,965
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	67,102	56,645
Depreciation and amortization	(15,675)	(14,951)
Operating Segments \| Consumer and Professional Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	21,926	20,565
Depreciation and amortization	(8,231)	(7,806)
Operating Segments \| Home and Building Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	40,701	31,295
Depreciation and amortization	(4,800)	(4,509)
Operating Segments \| Defense Electronics
Segment Reporting Information [Line Items]
Adjusted EBITDA	4,475	4,785
Depreciation and amortization	(2,644)	(2,636)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Adjusted EBITDA	11,942	11,264
Net interest expense	(15,950)	(16,331)
Depreciation and amortization	(15,825)	(15,085)
Restructuring charges	$ (6,434)	$ 0

Earnings Before Income Tax, Depreciation And Amortization

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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The net amount of operating interest income (expense).

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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