DOCUMENT AND ENTITY INFORMATION - $ / shares	9 Months Ended
	Jul. 31, 2019	Aug. 27, 2019
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jul. 31, 2019
Document Transition Report	false
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2019
Amendment Flag	false
Entity Information [Line Items]
Entity File Number	001-04604
Entity Registrant Name	HEICO CORPORATION
Entity Incorporation, State or Country Code	FL
Entity Tax Identification Number	65-0341002
Entity Address, Address Line One	3000 Taft Street
Entity Address, City or Town	Hollywood
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33021
City Area Code	954
Local Phone Number	987-4000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000046619
Current Fiscal Year End Date	--10-31
Heico Common Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $.01 par value per share
Trading Symbol	HEI
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		53,812,187
Entity Common Stock Par Value	$ 0.01
Common Class A [Member]
Entity Information [Line Items]
Title of 12(b) Security	Class A Common Stock, $.01 par value per share
Trading Symbol	HEI.A
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		80,340,878
Entity Common Stock Par Value	$ 0.01