OPERATING SEGMENTS (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 31, 2020	Jan. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 506,275	$ 466,146
Depreciation	6,800	6,212
Amortization	14,783	13,825
Operating income	110,990	97,947
Capital expenditures	6,850	5,907
Corporate And Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(3,203)	(5,496)
Depreciation	255	251
Amortization	246	246
Operating income	(8,546)	(6,535)
Capital expenditures	5	0
Flight Support Group [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	301,067	287,213
Depreciation	3,617	3,355
Amortization	4,859	4,803
Operating income	62,045	52,880
Capital expenditures	4,118	2,849
Electronic Technologies Group [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	208,411	184,429
Depreciation	2,928	2,606
Amortization	9,678	8,776
Operating income	57,491	51,602
Capital expenditures	$ 2,727	$ 3,058

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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