BUSINESS SEGMENTS - Revenues (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			3
Revenue	$ 632,061	$ 574,970	$ 1,746,849	$ 1,635,125
Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue	328,929	273,710	844,917	777,916
Home and Building Products
Segment Reporting Information [Line Items]
Revenue	219,164	221,521	670,374	631,615
Defense Electronics
Segment Reporting Information [Line Items]
Revenue	$ 83,968	$ 79,739	$ 231,558	$ 225,594