CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY AND COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	Total	Redeemable Noncontrolling Interests [Member]	Common Stock [Member]	Common Stock [Member] Class A Common Stock [Member]	Capital In Excess Of Par Value [Member]	Deferred Compensation Obligation [Member]	HEICO Stock Held By Irrevocable Trust [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total Shareholders Equity [Member]
Beginning Balance at Oct. 31, 2020			$ 542	$ 809	$ 299,930	$ 4,886	$ (4,886)	$ (9,149)	$ 1,688,045	$ 30,430	$ 2,010,607
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 224,042							5,884	218,158
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	18,425	$ 13,808								4,617
Comprehensive income	242,467										228,659
Cash dividends									(23,002)		(23,002)
Issuance of common stock to Savings and Investment Plan					8,216						8,216
Share-based compensation expense					6,354						6,354
Proceeds from stock option exercises				3							4,505
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					4,502
Stock Redeemed or Called During Period, Value					(3,687)						(3,687)
Distributions to noncontrolling interests		(20,122)								(1,731)	(1,731)
Value of Stock Issued or Reversed During Period for Deferred Compensation Obligation						(109)
Value of Stock Reversed During Period Deferred Compensation Obligation							109
Adjustments to redemption amount of redeemable noncontrolling interests		9,962							(9,962)		(9,962)
Adjustments to Additional Paid in Capital, Other					286
Stockholders' Equity, Other										(159)	127
Ending Balance at Jul. 31, 2021			542	812	315,601	4,777	(4,777)	(3,265)	1,873,239	33,157	2,220,086
Starting Balance, Redeemable Noncontrolling Interests at Oct. 31, 2020		221,208
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	18,425	13,808								4,617
Distributions to noncontrolling interests		(20,122)								(1,731)	(1,731)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(2,336)
Noncontrolling Interest, Increase from Business Combination	1,097
Adjustments to redemption amount of redeemable noncontrolling interests		9,962							(9,962)		(9,962)
Temporary Equity, Stock Issued During Period, Value, New Issues	$ 1,067
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2021		224,684
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.17
Beginning Balance at Apr. 30, 2021			542	811	311,995	4,777	(4,777)	1,674	1,812,798	32,070	2,159,890
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 71,950							(4,939)	76,889
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	6,621	4,747								1,874
Comprehensive income	78,571										73,824
Cash dividends									(12,184)		(12,184)
Issuance of common stock to Savings and Investment Plan					776						776
Share-based compensation expense					2,083						2,083
Proceeds from stock option exercises				1							667
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					666
Stock Redeemed or Called During Period, Value					(63)						(63)
Distributions to noncontrolling interests		(7,402)								(628)	(628)
Adjustments to redemption amount of redeemable noncontrolling interests		4,264							(4,264)		(4,264)
Adjustments to Additional Paid in Capital, Other					144
Stockholders' Equity, Other										(159)	(15)
Ending Balance at Jul. 31, 2021			542	812	315,601	4,777	(4,777)	(3,265)	1,873,239	33,157	2,220,086
Starting Balance, Redeemable Noncontrolling Interests at Apr. 30, 2021		223,266
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	6,621	4,747								1,874
Distributions to noncontrolling interests		(7,402)								(628)	(628)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(2,336)
Noncontrolling Interest, Increase from Business Combination	1,097
Adjustments to redemption amount of redeemable noncontrolling interests		4,264							(4,264)		(4,264)
Temporary Equity, Stock Issued During Period, Value, New Issues	1,067
Temporary Equity, Other Changes	$ (19)
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2021		224,684
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.09
Beginning Balance 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 Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	225,096							(29,375)	254,471
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	24,631	17,639								6,992
Comprehensive income	249,727										232,088
Cash dividends									(24,466)		(24,466)
Issuance of common stock to Savings and Investment Plan				1	9,497						9,498
Share-based compensation expense					9,815						9,815
Proceeds from stock option exercises			3	3							1,870
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					1,864
Stock Redeemed or Called During Period, Value			(1)	(1)	(25,824)						(25,826)
Distributions to noncontrolling interests		(15,759)								(1,007)	(1,007)
Increase to APIC from Purchase of Noncontrolling Interests and Net Assets					3,415						3,415
Adjustments to redemption amount of redeemable noncontrolling interests		8,194							(8,194)		(8,194)
Adjustments to Additional Paid in Capital, Other					(2,149)
Stockholders' Equity, Other									1		(2,148)
Ending Balance at Jul. 31, 2022	2,491,984		545	815	317,365	5,297	(5,297)	(37,927)	2,171,333	39,853	2,491,984
Starting Balance, Redeemable Noncontrolling Interests at Oct. 31, 2021	252,587	252,587
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	24,631	17,639								6,992
Distributions to noncontrolling interests		(15,759)								(1,007)	(1,007)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(12,150)
Noncontrolling Interest, Increase from Business Combination	42,719
Adjustments to redemption amount of redeemable noncontrolling interests		8,194							(8,194)		(8,194)
Temporary Equity, Other Changes	3,764
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2022	$ 296,994	296,994
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.18
Beginning Balance at Apr. 30, 2022			545	814	311,053	5,297	(5,297)	(30,554)	2,100,178	38,438	2,420,474
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 75,167							(7,373)	82,540
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	10,191	8,377								1,814
Comprehensive income	85,358										76,981
Cash dividends									(12,239)		(12,239)
Issuance of common stock to Savings and Investment Plan				1	1,758						1,759
Share-based compensation expense					2,960						2,960
Proceeds from stock option exercises											260
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					260
Stock Redeemed or Called During Period, Value					(2,134)						(2,134)
Distributions to noncontrolling interests		(5,791)								(399)	(399)
Increase to APIC from Purchase of Noncontrolling Interests and Net Assets					3,415						3,415
Adjustments to redemption amount of redeemable noncontrolling interests		(853)							853		853
Adjustments to Additional Paid in Capital, Other					53
Stockholders' Equity, Other									1		54
Ending Balance at Jul. 31, 2022	2,491,984		$ 545	$ 815	$ 317,365	$ 5,297	$ (5,297)	$ (37,927)	2,171,333	39,853	2,491,984
Starting Balance, Redeemable Noncontrolling Interests at Apr. 30, 2022		303,927
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	10,191	8,377								1,814
Distributions to noncontrolling interests		(5,791)								$ (399)	(399)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(12,150)
Noncontrolling Interest, Increase from Business Combination	3,484
Adjustments to redemption amount of redeemable noncontrolling interests		(853)							$ 853		$ 853
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2022	$ 296,994	$ 296,994
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.09