OPERATING SEGMENTS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 386,410	$ 532,324	$ 1,360,831	$ 1,514,118
Depreciation	6,711	6,440	20,276	19,096
Amortization	15,231	14,698	44,942	42,590
Operating Income (Loss)	68,434	119,414	287,585	336,544
Capital expenditures	5,037	9,075	17,472	21,671
Corporate And Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(2,667)	(3,821)	(8,643)	(16,371)
Depreciation	249	251	760	754
Amortization	246	246	738	738
Operating Income (Loss)	(5,518)	(7,589)	(18,960)	(24,459)
Capital expenditures	12	55	17	63
Flight Support Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	178,158	320,016	731,189	915,480
Depreciation	3,590	3,467	10,835	10,225
Amortization	5,109	4,991	14,720	14,714
Operating Income (Loss)	12,021	64,797	121,597	179,843
Capital expenditures	1,624	6,024	8,389	12,600
Electronic Technologies Group [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	210,919	216,129	638,285	615,009
Depreciation	2,872	2,722	8,681	8,117
Amortization	9,876	9,461	29,484	27,138
Operating Income (Loss)	61,931	62,206	184,948	181,160
Capital expenditures	$ 3,401	$ 2,996	$ 9,066	$ 9,008