ACQUISITIONS (Details Textuals)	9 Months Ended
Jul. 31, 2021
Heico Flight Support Corp \| Camtronics
Business Acquisition [Line Items]
Name of Acquired Entity	Camtronics, LLC
Description of Acquired Entity	Camtronics is a Federal Aviation Administration ("FAA")-certified Part 145 repair station with extensive proprietary FAA-designated engineering representative repairs for a variety of domestic and international commercial and cargo airlines.
Percentage of Voting Interests Acquired	80.10%
Heico Flight Support Corp \| Camtronics \| Noncontrolling interest holders in subsidiary one
Business Acquisition [Line Items]
Ownership Percentage by Noncontrolling Owners	9.90%
Heico Flight Support Corp \| Camtronics \| Exisiting Management
Business Acquisition [Line Items]
Ownership Percentage by Noncontrolling Owners	10.00%
Heico Flight Support Corp \| Subsidiary one
Business Acquisition [Line Items]
Percentage of Voting Interests Acquired	84.00%
Electronic Technologies Group [Member] \| Pyramid
Business Acquisition [Line Items]
Name of Acquired Entity	Pyramid Semiconductor LLC
Description of Acquired Entity	Pyramid is a specialty semiconductor designer and manufacturer offering a well-developed line of processors, static random-access memory (SRAM), electronically erasable programmable read-only memory (EEPROM) and Logic products on a diverse array of military, space and medical platforms.

With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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