OPERATING SEGMENTS (Last three years, segment information) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 31, 2020	Jul. 31, 2020	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Segment Reporting, Reconciling Item For Operating Profit (Loss) and Capital Expenditure From Segment To Consolidated [Line Items]
Net sales	$ 426,178	$ 386,410	$ 468,146	$ 506,275	$ 541,529	$ 532,324	$ 515,648	$ 466,146	$ 1,787,009	$ 2,055,647	$ 1,777,721
Depreciation									27,067	25,758	23,239
Amortization									61,494	57,739	53,952
Operating income									376,648	457,097	376,245
Capital expenditures									22,940	28,938	41,871
Flight Support Group [Member]
Segment Reporting, Reconciling Item For Operating Profit (Loss) and Capital Expenditure From Segment To Consolidated [Line Items]
Net sales									924,812	1,240,183	1,097,937
Depreciation									14,339	13,793	13,322
Amortization									19,957	19,624	19,530
Operating income									143,051	242,029	206,623
Capital expenditures									10,843	17,036	13,074
Electronic Technologies Group [Member]
Segment Reporting, Reconciling Item For Operating Profit (Loss) and Capital Expenditure From Segment To Consolidated [Line Items]
Net sales									874,987	834,522	701,827
Depreciation									11,722	10,957	9,225
Amortization									40,553	37,131	33,339
Operating income									258,814	245,743	204,508
Capital expenditures									12,025	11,826	9,531
Other Primarily Corporate and Inter Segment [Member]
Segment Reporting, Reconciling Item For Operating Profit (Loss) and Capital Expenditure From Segment To Consolidated [Line Items]
Depreciation									1,006	1,008	692
Amortization									984	984	1,083
Operating income									(25,217)	(30,675)	(34,886)
Capital expenditures									72	76	19,266
Consolidation, Eliminations [Member] | Other Primarily Corporate and Inter Segment [Member]
Segment Reporting, Reconciling Item For Operating Profit (Loss) and Capital Expenditure From Segment To Consolidated [Line Items]
Net sales									$ (12,790)	$ (19,058)	$ (22,043)