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, 2023			$ 547	$ 835	$ 578,809	$ 6,318	$ (6,318)	$ (40,180)	$ 2,605,984	$ 47,156	$ 3,193,151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 385,656							11,235	374,421
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	34,155	$ 23,725								10,430
Comprehensive income	419,811										396,086
Cash dividends									(29,069)		(29,069)
Issuance of common stock to Savings and Investment Plan					11,613						11,613
Share-based compensation expense					14,088						14,088
Proceeds from stock option exercises			1	2							6,387
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					6,384
Redemptions of common stock related to stock option exercises					(4,836)						(4,836)
Distributions to noncontrolling interests		(22,699)								(656)	(656)
Adjustments to redemption amount of redeemable noncontrolling interests		(2,082)							2,082		2,082
Adjustments to Additional Paid in Capital, Other					7,624
Stockholders' Equity, Other									436		8,060
Ending Balance at Jul. 31, 2024			548	837	613,682	6,318	(6,318)	(28,945)	2,953,854	56,930	3,596,906
Starting Balance, Redeemable Noncontrolling Interests at Oct. 31, 2023		364,807
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	34,155	23,725								10,430
Distributions to noncontrolling interests		(22,699)								(656)	(656)
Acquisitions of noncontrolling interests, RNCI		(26,567)
Adjustments to redemption amount of redeemable noncontrolling interests		(2,082)							2,082		2,082
Temporary Equity, Other Changes	$ (7,913)
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2024		329,271
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.21
Beginning Balance at Apr. 30, 2024			548	836	598,699	6,318	(6,318)	(35,677)	2,825,021	53,379	3,442,806
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 143,309							6,732	136,577
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	11,475	7,726								3,749
Comprehensive income	154,784										147,058
Cash dividends									(15,238)		(15,238)
Issuance of common stock to Savings and Investment Plan					2,313						2,313
Share-based compensation expense					4,625						4,625
Proceeds from stock option exercises				1							2,236
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					2,235
Redemptions of common stock related to stock option exercises					(2,484)						(2,484)
Distributions to noncontrolling interests		(23,402)								(198)
Increase to APIC from Purchase of Noncontrolling Interests and Net Assets											(198)
Adjustments to redemption amount of redeemable noncontrolling interests		(6,690)							6,690		6,690
Adjustments to Additional Paid in Capital, Other	8,294
Stockholders' Equity, Other									804		9,098
Ending Balance at Jul. 31, 2024			548	837	613,682	6,318	(6,318)	(28,945)	2,953,854	56,930	3,596,906
Starting Balance, Redeemable Noncontrolling Interests at Apr. 30, 2024		368,369
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	11,475	7,726								3,749
Distributions to noncontrolling interests		(23,402)								(198)
Acquisitions of noncontrolling interests, RNCI	(7,732)
Adjustments to redemption amount of redeemable noncontrolling interests		(6,690)							6,690		6,690
Temporary Equity, Other Changes	$ (9,000)
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2024		329,271
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.11
Beginning Balance at Oct. 31, 2024	$ 3,697,406		550	838	599,399	7,272	(7,272)	(26,076)	3,062,166	60,529	3,697,406
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	529,047							26,958	502,089
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	40,889	28,883								12,006
Comprehensive income	569,936										541,053
Cash dividends									(31,968)		(31,968)
Issuance of common stock to Savings and Investment Plan			1	1	15,937						15,939
Share-based compensation expense					18,346						18,346
Issuance of common stock for an acquisition				1	10,122						10,123
Proceeds from stock option exercises				2							11,680
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					11,678
Redemptions of common stock related to stock option exercises					(1,979)						(1,979)
Distributions to noncontrolling interests		(25,514)								(1,448)	(1,448)
Adjustments to redemption amount of redeemable noncontrolling interests		43,129							(43,129)		(43,129)
Adjustments to Additional Paid in Capital, Other					(3,189)
Stockholders' Equity, Other									(381)		(3,570)
Ending Balance at Jul. 31, 2025	4,212,453		551	842	650,314	7,272	(7,272)	882	3,488,777	71,087	4,212,453
Starting Balance, Redeemable Noncontrolling Interests at Oct. 31, 2024	366,156	366,156
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	40,889	28,883								12,006
Noncontrolling interests assumed related to acquisitions	27,906
Distributions to noncontrolling interests		(25,514)								(1,448)	(1,448)
Acquisitions of noncontrolling interests, RNCI		(5,773)
Adjustments to redemption amount of redeemable noncontrolling interests		43,129							(43,129)		(43,129)
Temporary Equity, Other Changes	2,800
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2025	$ 437,587	437,587
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.23
Beginning Balance at Apr. 30, 2025			550	840	637,981	7,272	(7,272)	(411)	3,328,591	67,756	4,035,307
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 178,634							1,293	177,341
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	12,934	9,423								3,511
Comprehensive income	191,568										182,145
Cash dividends									(16,696)		(16,696)
Issuance of common stock to Savings and Investment Plan			1	1	2,875						2,877
Share-based compensation expense					7,675						7,675
Proceeds from stock option exercises				1							5,894
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					5,893
Redemptions of common stock related to stock option exercises					(564)						(564)
Distributions to noncontrolling interests		(9,506)								(180)	(180)
Adjustments to redemption amount of redeemable noncontrolling interests		320							(320)		(320)
Adjustments to Additional Paid in Capital, Other					(3,546)
Stockholders' Equity, Other									(139)		(3,685)
Ending Balance at Jul. 31, 2025	4,212,453		$ 551	$ 842	$ 650,314	$ 7,272	$ (7,272)	$ 882	3,488,777	71,087	4,212,453
Starting Balance, Redeemable Noncontrolling Interests at Apr. 30, 2025		436,471
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	12,934	9,423								3,511
Noncontrolling interests assumed related to acquisitions	29
Distributions to noncontrolling interests		(9,506)								$ (180)	(180)
Acquisitions of noncontrolling interests, RNCI		(1,568)
Adjustments to redemption amount of redeemable noncontrolling interests		320							$ (320)		$ (320)
Temporary Equity, Other Changes	2,418
Ending Balance, Redeemable Noncontrolling Interests at Jul. 31, 2025	$ 437,587	$ 437,587
Increase (Decrease) in Temporary Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.12