CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Redeemable Noncontrolling Interests [Member]	Redeemable Noncontrolling Interests [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Common Stock [Member] Common Class A [Member]	Capital in Excess of Par Value [Member]	Deferred Compensation Obligation [Member]	HEICO Stock Held By Irrevocable Trust [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Total Shareholders Equity [Member]	Total Shareholders Equity [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]
Balances at Oct. 31, 2018				$ 534	$ 796	$ 320,994	$ 3,928	$ (3,928)	$ (15,256)	$ 1,091,183		$ 104,757		$ 1,503,008
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 326,413								(1,483)	327,896
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	31,620	$ 18,116										13,504
Comprehensive Income (Loss)	358,033													339,917
Cash dividends										(18,691)				(18,691)
Issuance of Common Stock to HEICO SIP						8,666								8,666
Share-based Compensation Expense						10,334								10,334
Proceeds from stock option exercises				12	8									8,547
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition						8,527
Stock Redeemed or Called During Period, Value				(5)	(1)	(64,008)								(64,014)
Distributions to noncontrolling interests	(17,847)											(93,022)		(93,022)
Noncontrolling interests assumed related to acquisition		(38,696)										(2,551)		(2,551)
Adjustments to redemption amount of redeemable noncontrolling interests	16,434									(16,434)				(16,434)
Deferred Compensation Obligation							304
Stock Held During Period Value Deferred Compensation Obligation								(304)
Adjustments to Additional Paid in Capital, Other						96
Stockholders' Equity, Other					1							2		99
Balances at Oct. 31, 2019				541	804	284,609	4,232	(4,232)	(16,739)	1,397,327		28,118		1,694,660
Balances (Accounting Standards Update 2014-09 [Member]) at Oct. 31, 2019											$ 13,373				$ 13,699
Redeemable noncontrolling interests at Oct. 31, 2018		132,046
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Redeemable Noncontrolling Interest	31,620	18,116										13,504
Distributions to noncontrolling interests	(17,847)											(93,022)		(93,022)
Noncontrolling interests assumed related to acquisition		38,696										2,551		2,551
Adjustments to redemption amount of redeemable noncontrolling interests	16,434									(16,434)				(16,434)
Redeemable noncontrolling interests at Oct. 31, 2019		188,264
Redeemable noncontrolling interests (Accounting Standards Update 2014-09 [Member]) at Oct. 31, 2019			$ 819										$ 326
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	321,574								7,590	313,984
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	22,218	16,932										5,286
Comprehensive Income (Loss)	343,792													326,860
Cash dividends										(21,552)				(21,552)
Issuance of Common Stock to HEICO SIP				1		9,723								9,724
Share-based Compensation Expense						10,134								10,134
Proceeds from stock option exercises					6									6,955
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition						6,949
Stock Redeemed or Called During Period, Value					(1)	(12,119)								(12,120)
Distributions to noncontrolling interests	(16,176)											(1,732)		(1,732)
Noncontrolling interests assumed related to acquisition		(22,204)
Adjustments to redemption amount of redeemable noncontrolling interests	1,714									(1,714)				(1,714)
Deferred Compensation Obligation							654
Stock Held During Period Value Deferred Compensation Obligation								(654)
Adjustments to Additional Paid in Capital, Other						634
Stockholders' Equity, Other												(1,242)		(608)
Balances at Oct. 31, 2020	2,010,607			542	809	299,930	4,886	(4,886)	(9,149)	1,688,045		30,430		2,010,607
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Redeemable Noncontrolling Interest	22,218	16,932										5,286
Distributions to noncontrolling interests	(16,176)											(1,732)		(1,732)
Acquisitions of noncontrolling interests	(7,475)
Noncontrolling interests assumed related to acquisition		22,204
Adjustments to redemption amount of redeemable noncontrolling interests	1,714									(1,714)				(1,714)
Temporary Equity, Stock Issued During Period, Value, New Issues	14,329
Temporary Equity, Other	1,416
Redeemable noncontrolling interests at Oct. 31, 2020	221,208	221,208
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	304,817								597	304,220
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	25,476	19,662										5,814
Comprehensive Income (Loss)	330,293													310,631
Cash dividends										(23,002)				(23,002)
Issuance of Common Stock to HEICO SIP				1		9,791								9,792
Share-based Compensation Expense						9,058								9,058
Proceeds from stock option exercises					3									5,344
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition						5,341
Stock Redeemed or Called During Period, Value						(3,791)								(3,791)
Distributions to noncontrolling interests	(25,746)											(2,217)		(2,217)
Noncontrolling interests assumed related to acquisition		(18,989)
Adjustments to redemption amount of redeemable noncontrolling interests	19,743									(19,743)				(19,743)
Deferred Compensation Obligation							411
Stock Held During Period Value Deferred Compensation Obligation								(411)
Adjustments to Additional Paid in Capital, Other						418
Stockholders' Equity, Other										1		(159)		260
Balances at Oct. 31, 2021	2,296,939			$ 543	$ 812	$ 320,747	$ 5,297	$ (5,297)	$ (8,552)	1,949,521		33,868		2,296,939
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Redeemable Noncontrolling Interest	25,476	19,662										5,814
Distributions to noncontrolling interests	(25,746)											$ (2,217)		(2,217)
Acquisitions of noncontrolling interests	(2,336)
Noncontrolling interests assumed related to acquisition		18,989
Adjustments to redemption amount of redeemable noncontrolling interests	19,743									$ (19,743)				$ (19,743)
Temporary Equity, Stock Issued During Period, Value, New Issues	1,067
Redeemable noncontrolling interests at Oct. 31, 2021	$ 252,587	$ 252,587