ACQUISITIONS ACQUISITIONS (Pro Forma Information) (Details) - HEICO Electronic [Member] - AAT [Member] $ / shares in Units, $ in Thousands	12 Months Ended
Oct. 31, 2017 USD ($) $ / shares
Business Acquisition [Line Items]
Pro Forma Revenue	$ 1,582,653
Pro Forma Net Income (Loss) Attributable to HEICO	220,419
Pro Forma Net Income Attributable to Parent	$ 198,744
Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders [Abstract]
Pro Forma Earnings Per Share, Basic \| $ / shares	$ 1.51
Pro Forma Earnings Per Share, Diluted \| $ / shares	$ 1.47

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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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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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