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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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Purchase price of expected business acquisition prior to consideration being transferred. Excludes asset acquisition.

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Amount of liabilities assumed at the acquisition date.

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

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ACQUISITIONS (Details Textuals) € in Thousands, $ in Thousands	3 Months Ended			9 Months Ended
	Jan. 31, 2023 USD ($)	Jan. 31, 2023 EUR (€)	Jul. 31, 2021 USD ($)	Jul. 31, 2022 USD ($)	Jul. 31, 2021 USD ($)	Jan. 31, 2023 EUR (€)
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue			$ 504,100		$ 1,448,000
Business Acquisition, Pro Forma Net Income (Loss)			$ 88,100		$ 248,500
Heico Flight Support Corp \| Accurate
Business Acquisition [Line Items]
Name of Acquired Entity				Accurate Metal Machining, Inc.
Description of Acquired Entity				Accurate is a manufacturer of high-reliability components and assemblies.
Business Acquisition, Percentage of Voting Interests Acquired				96.00%
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				$ 13,100
Heico Flight Support Corp \| Accurate \| Existing Management
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				4.00%
Heico Flight Support Corp \| Pioneer
Business Acquisition [Line Items]
Name of Acquired Entity				Pioneer Industries, LLC
Description of Acquired Entity				Pioneer is a specialty distributor of spares for military aviation, marine, and ground platforms.
Business Acquisition, Percentage of Voting Interests Acquired				74.00%
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				$ 9,800
Heico Flight Support Corp \| Pioneer \| Existing Management
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				26.00%
Heico Electronic Technologies Corp \| Exxelia
Business Acquisition [Line Items]
Name of Acquired Entity				Exxelia International
Description of Acquired Entity				Exxelia designs, manufactures and sells high-reliability (“Hi-Rel”), complex, passive electronic components and rotary joint assemblies for mostly aerospace and defense applications, in addition to other high-end applications, such as medical and energy uses, including emerging “clean energy” and electrification applications.
Heico Electronic Technologies Corp \| Exxelia \| Subsequent Event \| Forecast
Business Acquisition [Line Items]
Business Combination, Price of Acquisition, Expected	$ 463,100	€ 453,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	$ 14,300					€ 14,000
Heico Electronic Technologies Corp \| Exxelia \| Existing Management \| Subsequent Event \| Forecast
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%					5.00%
Heico Electronic Technologies Corp \| Flight Microwave
Business Acquisition [Line Items]
Name of Acquired Entity				Flight Microwave Corporation
Description of Acquired Entity				Flight Microwave is a designer and manufacturer of custom high power filters and filter assemblies used in space and defense applications.
Business Acquisition, Percentage of Voting Interests Acquired				100.00%