Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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

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No definition available.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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No definition available.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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SHAREHOLDERS' EQUITY (Details Textuals) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Jun. 28, 2019	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2019
Stockholders' Equity Note [Abstract]
Stock repurchase program, number of shares authorized to be repurchased (in shares)		4,886,353
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				476,586
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation				$ 53,100
HEICO Aerospace [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	80.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	20.00%	20.00%
HEICO Aerospace [Member] \| Eight Acquired FSG Subsidiaries [Member]
Noncontrolling Interest [Line Items]
Total purchase consideration	$ 91,500
Business Acquisition, Percentage of Voting Interests Acquired				20.00%
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		32,355	127,851	111,730
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation		$ 3,800	$ 12,100	$ 10,900