QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details Textuals) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Oct. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Deferred Tax Expense from Stock Options Exercised	$ 16.6
Transition Tax Expense from Unremitted Earnings from Foreign Subsidiaries		$ 11.9	$ 4.4
Remeasurement of Deferred Tax Liabilities for Change in Tax Rate, Net, Per Share		$ 0.09
Net income attributable to HEICO	$ 15.1	$ 2.1
Earnings Per Share, Basic	$ 0.11	$ 0.02

Net income from discrete tax benefit from stock option exercises

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Net income from discrete tax benefit from stock option exercises, per share, basic and diluted

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Transition Tax Expense from Unremitted Earnings from Foreign Subsidiaries

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Transition tax expense from unremitted foreign subsidiaries, basic and diluted earnings per share

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Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

No definition available.

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