OPERATING SEGMENTS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Segment Reporting Information [Line Items]
Revenues	$ 468,146	$ 515,648	$ 974,421	$ 981,794
Depreciation	6,765	6,444	13,565	12,656
Amortization	14,928	14,067	29,711	27,892
Operating Income (Loss)	108,161	119,183	219,151	217,130
Capital expenditures	5,585	6,689	12,435	12,596
Corporate And Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(2,773)	(7,054)	(5,976)	(12,550)
Depreciation	256	252	511	503
Amortization	246	246	492	492
Operating Income (Loss)	(4,896)	(10,335)	(13,442)	(16,870)
Capital expenditures	0	8	5	8
Flight Support Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	251,964	308,251	553,031	595,464
Depreciation	3,628	3,403	7,245	6,758
Amortization	4,752	4,920	9,611	9,723
Operating Income (Loss)	47,531	62,166	109,576	115,046
Capital expenditures	2,647	3,727	6,765	6,576
Electronic Technologies Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	218,955	214,451	427,366	398,880
Depreciation	2,881	2,789	5,809	5,395
Amortization	9,930	8,901	19,608	17,677
Operating Income (Loss)	65,526	67,352	123,017	118,954
Capital expenditures	$ 2,938	$ 2,954	$ 5,665	$ 6,012