OPERATING SEGMENTS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 532,324	$ 465,825	$ 1,514,118	$ 1,300,837
Depreciation	6,440	5,747	19,096	17,099
Amortization	14,698	13,687	42,590	40,424
Operating income	119,414	101,423	336,544	272,548
Capital expenditures	9,075	6,441	21,671	35,898
Corporate And Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(3,821)	(5,671)	(16,371)	(17,596)
Depreciation	251	253	754	439
Amortization	246	246	738	837
Operating income	(7,589)	(9,310)	(24,459)	(26,892)
Capital expenditures	55	0	63	19,266
Flight Support Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	320,016	285,126	915,480	807,683
Depreciation	3,467	3,237	10,225	9,819
Amortization	4,991	4,850	14,714	14,729
Operating income	64,797	54,712	179,843	152,069
Capital expenditures	6,024	3,504	12,600	9,710
Electronic Technologies Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	216,129	186,370	615,009	510,750
Depreciation	2,722	2,257	8,117	6,841
Amortization	9,461	8,591	27,138	24,858
Operating income	62,206	56,021	181,160	147,371
Capital expenditures	$ 2,996	$ 2,937	$ 9,008	$ 6,922