BUSINESS SEGMENTS - Depreciation, Amortization And Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Segment depreciation and amortization	$ 13,313	$ 12,147	$ 26,271	$ 24,135
CAPITAL EXPENDITURES	10,843	7,848	21,628	15,538
Home And Building Products [Member]
Segment Reporting Information [Line Items]
Segment depreciation and amortization	10,504	9,251	20,637	18,418
CAPITAL EXPENDITURES	8,192	3,768	14,850	10,159
Telephonics [Member]
Segment Reporting Information [Line Items]
Segment depreciation and amortization	2,695	2,771	5,414	5,488
CAPITAL EXPENDITURES	2,442	1,817	4,385	3,113
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment depreciation and amortization	13,199	12,022	26,051	23,906
CAPITAL EXPENDITURES	10,634	5,585	19,235	13,272
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Segment depreciation and amortization	114	125	220	229
CAPITAL EXPENDITURES	$ 209	$ 2,263	$ 2,393	$ 2,266

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

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.

+ References

No definition available.

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