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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as current.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The amortization method of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company. The straight-line method is the preferred amortization method, unless another method better reflects the pattern in which the asset is consumed.

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

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The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Textuals) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Depreciation Methods									Depreciation and amortization is generally provided on the straight-line method over the estimated useful lives of the various assets.
Business Combination, Description [Abstract]
Business Acquisition, Transaction Costs					$ 3,200					$ 3,200
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Amortization Method									The Company’s intangible assets subject to amortization are amortized on the straight-line method (except for certain customer relationships amortized on an accelerated method) over the following estimated useful lives
Revenue Recognition [Abstract]
Percent of Revenue from Services Renderred									10.00%
Net Sales Recognized from Percentage-Of-Completion Method									3.00%	3.00%	4.00%
Stockholders' Equity Note, Stock Split, Conversion Ratio									0.25
Net income attributable to HEICO	$ 53,674	$ 45,698	$ 45,686	$ 40,927	44,262	$ 42,002	$ 38,657	$ 31,271	$ 185,985	$ 156,192	$ 133,364
Weighted Average Number of Shares Outstanding, Diluted									86,776,000	85,213,000	84,764,000
Lufthansa Technik AG [Member] \| Heico Aerospace [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Percentage of interest owned by noncontrolling shareholders	20.00%								20.00%
Heico Flight Support Corp [Member] \| Subsidiaries [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	80.10%								80.10%
Heico Flight Support Corp [Member] \| Subsidiary One [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	80.00%								80.00%
Heico Flight Support Corp [Member] \| Subsidiary Two [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	84.00%								84.00%
HEICO Electronic [Member] \| Subsidiary One [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	80.10%								80.10%
HEICO Electronic [Member] \| Subsidiary Two [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	80.10%								80.10%
HEICO Electronic [Member] \| Subsidiary Three [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	82.50%								82.50%
HEICO Electronic [Member] \| Subsidiary Four [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	95.90%								95.90%
HEICO Electronic [Member] \| Subsidiary Five [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	78.00%								78.00%
Heico Aerospace [Member] \| Subsidiary One [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	80.10%								80.10%
Heico Aerospace [Member] \| Subsidiary Two [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	82.30%								82.30%
Heico Aerospace [Member] \| Joint Venture [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Noncontrolling Interest, Ownership Percentage by Parent	84.00%								84.00%
Accounting Standards Update 2015-17 [Member]
Revenue Recognition [Abstract]
Deferred Tax Assets, Net of Valuation Allowance, Current					$ 41,100					$ 41,100
Accounting Standards Update 2016-09 [Member]
Revenue Recognition [Abstract]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense				3,100
Net income attributable to HEICO				$ 2,600
Weighted Average Number of Shares Outstanding, Diluted				679,000					781,000
Share-based Compensation									$ 3,100
Proceeds and Excess Tax Benefit from Share-based Compensation									$ 3,100