ACQUISITIONS (Details Textuals) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2019
Business Acquisition [Line Items]
Net sales	$ 1,865,682	$ 1,787,009	$ 2,055,647
Net income	304,220	313,984	327,896
Payments to Acquire Businesses, Net of Cash Acquired	136,500	163,939	$ 240,841
Contingent consideration, liability	$ 62,286	$ 41,974
Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years	10 years	11 years
Intellectual Property [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	13 years	11 years	15 years
HEICO Electronic [Member] | Subsidiary Three [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	80.10%
HEICO Electronic [Member] | Paciwave [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Paciwave, Inc.
Description of Acquired Entity	Paciwave is a designer and manufacturer of Radio Frequency (RF) and microwave components and integrated assemblies specializing particularly in PIN Diode Switches, PIN Attenuators, PIN Limiters, Switching Assemblies and integrated subsystems found in defense and other complex electronic applications.
HEICO Electronic [Member] | RH Labs [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	R.H. Laboratories, Inc.
Description of Acquired Entity	RH Labs designs and manufactures state-of-the-art RF and microwave integrated assemblies, sub-assemblies and components used in a broad range of demanding defense applications operating in harsh environments including Space.
Business Acquisition, Percentage of Voting Interests Acquired	80.10%
HEICO Electronic [Member] | RH Labs [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	19.90%
HEICO Electronic [Member] | Pyramid [Member]
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.
HEICO Electronic [Member] | Connect Tech [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Connect Tech Inc.
Description of Acquired Entity	Connect Tech designs and manufacturers rugged, small-form-factor embedded computing solutions. Connect Tech's components are designed for very harsh environments and are primarily used in rugged commercial and industrial, aerospace and defense, transportation, and smart energy applications.
Amount of contingent purchase consideration, the company could be required to pay	$ 9,700
Business Acquisition, Percentage of Voting Interests Acquired	89.99%
HEICO Electronic [Member] | Connect Tech [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	10.01%
HEICO Electronic [Member] | TSID [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Transformational Security, LLC and Intelligent Devices, Inc. (collectively, "TSID")
Description of Acquired Entity	TSID develops and manufactures state-of-the-art Technical Surveillance Countermeasures ("TSCM") equipment used to protect critical spaces from exploitation via wireless transmissions, technical surveillance and listening devices.
Amount of contingent purchase consideration, the company could be required to pay	$ 14,000
Business Acquisition, Percentage of Voting Interests Acquired	75.00%
HEICO Electronic [Member] | TSID [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	25.00%
HEICO Electronic [Member] | Transformational Security [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Transformational Security, LLC
HEICO Electronic [Member] | Intelligent Devices [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Intelligent Devices, Inc.
HEICO Electronic [Member] | Freebird [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Freebird Semiconductor Corporation
Description of Acquired Entity	Freebird is a fabless design and manufacturing company that offers advanced high-reliability wide-band gap power switching technology.
Business Acquisition, Percentage of Voting Interests Acquired	50.00%
HEICO Electronic [Member] | EPC [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	EPC Space LLC
Description of Acquired Entity	EPC designs, develops, promotes, markets and sells radiation-hardened gallium nitride power solutions packaged for use in outer space and other high reliability applications.
Business Acquisition, Percentage of Voting Interests Acquired	49.00%
HEICO Electronic [Member] | HMI [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Human-Machine Interface
Description of Acquired Entity	HMI designs, manufactures, and repairs flight deck annunciators, panels, indicators, and illuminated keyboards, as well as lighting controls, and flight deck lighting.
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
HEICO Electronic [Member] | Quell [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Quell Corporation
Description of Acquired Entity	Quell designs and manufactures electromagnetic interference (EMI)/radio-frequency interference (RFI) and transient protection solutions for a wide variety of connectors that principally serve customers within the aerospace and defense markets.
Business Acquisition, Percentage of Voting Interests Acquired	80.10%
HEICO Electronic [Member] | Quell [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	19.90%
HEICO Electronic [Member] | TTT-Cubed [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	TTT-Cubed, Inc.
Description of Acquired Entity	TTT is a designer and manufacturer of RF Sources, Detectors, and Controllers for a certain wide range of aerospace and defense applications.
HEICO Electronic [Member] | Bernier Connect SAS [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Bernier Connect SAS
Description of Acquired Entity	Bernier is a designer and manufacturer of interconnect products used in demanding defense, aerospace and industrial applications, primarily for communications-related purposes.
HEICO Electronic [Member] | Moulages Plastiques Industriels [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Moulages Plastiques Industriels de L'essonne
Description of Acquired Entity	a plastics manufacturer ("MPI").
Business Acquisition, Percentage of Voting Interests Acquired	70.00%
HEICO Electronic [Member] | Research Electronics International [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Research Electronics International, LLC
Description of Acquired Entity	REI is a designer and manufacturer of TSCM equipment to detect devices used for espionage and information theft.
Business Acquisition, Percentage of Voting Interests Acquired	75.00%
HEICO Electronic [Member] | Research Electronics International [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	25.00%
HEICO Electronic [Member] | Solid Sealing Technology [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Solid Sealing Technology, Inc.
Description of Acquired Entity	SST designs and manufactures high-reliability ceramic-to-metal feedthroughs and connectors for demanding environments within the defense, industrial, life science, medical, research, semiconductor, and other markets.
Business Acquisition, Percentage of Voting Interests Acquired	85.00%
HEICO Electronic [Member] | Solid Sealing Technology [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	15.00%
HEICO Electronic [Member] | Apex [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Apex Microtechnology, Inc.
Description of Acquired Entity	Apex designs and manufactures precision power analog monolithic, hybrid and open frame components for a certain wide range of aerospace, defense, industrial, measurement, medical and test applications.
Business Acquisition, Percentage of Voting Interests Acquired	92.70%
HEICO Electronic [Member] | Apex [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	7.30%
HEICO Electronic [Member] | Specialty Silicone Products [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Specialty Silicone Products, Inc.
Description of Acquired Entity	SSP designs and manufactures silicone material for a variety of demanding applications used in aerospace, defense, research, oil and gas, testing, pharmaceuticals and other markets.
Heico Flight Support Corp [Member] | Subsidiary Three [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	84.00%
Heico Flight Support Corp [Member] | Ridge Holdco [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Ridge HoldCo, LLC
Amount of contingent purchase consideration, the company could be required to pay	$ 18,300
Business Acquisition, Percentage of Voting Interests Acquired	89.00%
Heico Flight Support Corp [Member] | Ridge Holdco [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	11.00%
Heico Flight Support Corp [Member] | Ridge Engineering [Member] | Ridge Holdco [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Ridge Engineering, Inc.
Description of Acquired Entity	Ridge performs tight-tolerance machining and brazing of large-sized parts in mission-critical defense and aerospace applications.
Heico Flight Support Corp [Member] | Bechdon [Member] | Ridge Holdco [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	The Bechdon Company, Inc.
Description of Acquired Entity	Bechdon provides machining, fabrication and welding services for aerospace, defense and other industrial applications.
Heico Flight Support Corp [Member] | Camtronics [Member]
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.
Business Acquisition, Percentage of Voting Interests Acquired	80.10%
Heico Flight Support Corp [Member] | Camtronics [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	10.00%
Heico Flight Support Corp [Member] | Camtronics [Member] | Subsidiary Three [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	9.90%
Heico Flight Support Corp [Member] | Rocky Mountain [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Rocky Mountain Hydrostatics, LLC
Description of Acquired Entity	Rocky Mountain overhauls industrial pumps, motors, and other hydraulic units with a focus on the support of legacy systems for the U.S. Navy.
Business Acquisition, Percentage of Voting Interests Acquired	70.00%
Heico Flight Support Corp [Member] | Rocky Mountain [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	30.00%
Heico Flight Support Corp [Member] | Decavo [Member]
Business Acquisition [Line Items]
Name of Acquired Entity	Decavo LLC
Description of Acquired Entity	Decavo designs and produces complex composite parts and assemblies incorporated into camera and related sensor assemblies and unmanned aerial vehicle ("UAV") airframes used in demanding defense and civilian applications.
Amount of contingent purchase consideration, the company could be required to pay	$ 2,100
Business Acquisition, Percentage of Voting Interests Acquired	80.10%
Heico Flight Support Corp [Member] | Decavo [Member] | Existing Management [Member]
Business Acquisition [Line Items]
Percentage of interest owned by noncontrolling shareholders	19.90%