ACQUISITIONS ACQUISITIONS (Details 3) - Electronic Technologies Group [Member] - AAT [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Oct. 31, 2017	Oct. 31, 2016
Business Acquisition [Line Items]
Pro Forma Revenue	$ 1,582,653	$ 1,428,336
Pro Forma Net Income (Loss) Attributable to HEICO	220,419	185,070
Pro Forma Net Income Attributable to Parent	$ 198,744	$ 165,112
Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders [Abstract]
Pro Forma Earnings Per Share, Basic	$ 2.36	$ 1.97
Pro Forma Earnings Per Share, Diluted	$ 2.29	$ 1.94

Business Acquisition Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders

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Pro Forma Net Income Attributable to Parent

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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 pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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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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