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ACQUISITIONS (Details Textuals) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
ACQUISITIONS (Details Textuals) - USD ($) $ in Thousands	Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2026	Apr. 30, 2025
Business Combination [Line Items]
Business Combination, Pro Forma Information, Pro Forma Revenue	$ 1,391,500	$ 1,158,900	$ 2,634,800	$ 2,249,000
Rockmart \| Heico Electronic Technologies Corp
Business Combination [Line Items]
Business Combination, Voting Equity Interest Acquired, Percentage	100.00%		100.00%
Business Combination, Name of Acquiree			Axillon Aerospace’s Fuel Containment Business
Business Combination, Description of Acquiree	renamed Rockmart Fuel Containment, LLC (“Rockmart”). Rockmart designs and manufactures advanced fuel containment solutions, primarily for military fixed- and rotary-wing aircraft.
Ethos \| HFSC
Business Combination [Line Items]
Business Combination, Voting Equity Interest Acquired, Percentage	100.00%		100.00%
Business Combination, Name of Acquiree			EthosEnergy Accessories and Components, LLC and 100% of the stock of EthosEnergy Accessories and Components, Limited (collectively, “Ethos”)
Business Combination, Description of Acquiree	Ethos provides repair solutions for engine components and accessories for various aeroderivative, aerospace, and defense engine platforms.
Stock Issued During Period, Shares, Acquisitions			95,483
Sherwood \| HFSC
Business Combination [Line Items]
Business Combination, Voting Equity Interest Acquired, Percentage	80.00%		80.00%
Business Combination, Name of Acquiree			Sherwood Avionics and Accessories, Inc.
Business Combination, Description of Acquiree	Sherwood is an FAA and EASA Part 145 repair station specializing in the maintenance, repair and overhaul of complex, mission-critical mechanical and electro-mechanical components for defense and select commercial aviation platforms.
Stock Issued During Period, Shares, Acquisitions			86,474
Sherwood \| HFSC \| Existing Management
Business Combination [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	20.00%		20.00%
SWA
Business Combination [Line Items]
Business Combination, Voting Equity Interest Acquired, Percentage	90.00%		90.00%
Business Combination, Name of Acquiree			Southwest Antennas, Inc.
Business Combination, Description of Acquiree	SWA designs and manufactures high-performance rugged and mission-critical antennas primarily for ground-based defense and law enforcement applications.
Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount	$ 2,700		$ 2,700
SWA \| Existing Management
Business Combination [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	10.00%		10.00%
FY 2026 Acquisitions \| Customer Relationships [Member]
Business Combination [Line Items]
Intangible Asset, Finite-Lived, Useful Life	12 years		12 years
FY 2026 Acquisitions \| Intellectual Property [Member]
Business Combination [Line Items]
Intangible Asset, Finite-Lived, Useful Life	15 years		15 years