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	$ 152,092							10,823	141,269
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	11,804	$ 9,061								2,743
Comprehensive income	163,896										154,835
Cash dividends									(10,818)		(10,818)
Issuance of common stock to Savings and Investment Plan					7,440						7,440
Share-based compensation expense					4,271						4,271
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					3,836
Proceeds from stock option exercises				2							3,838
Stock Redeemed or Called During Period, Value					(3,624)						(3,624)
Distributions to noncontrolling interests		(12,720)								(1,103)	(1,103)
Adjustments to redemption amount of redeemable noncontrolling interests		5,698							(5,698)		(5,698)
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 Additional Paid in Capital, Other					142						142
Ending Balance at Apr. 30, 2021			542	811	311,995	4,777	(4,777)	1,674	1,812,798	32,070	2,159,890
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	11,804	9,061								2,743
Distributions to noncontrolling interests		(12,720)								(1,103)	(1,103)
Adjustments to redemption amount of redeemable noncontrolling interests		5,698							(5,698)		(5,698)
Temporary Equity, Other Changes	19
Ending Balance, Redeemable Noncontrolling Interests at Apr. 30, 2021		223,266
Beginning Balance at Jan. 31, 2021			542	811	301,107	4,777	(4,777)	2,129	1,744,247	31,323	2,080,159
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	70,218							(455)	70,673
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	5,748	4,264								1,484
Comprehensive income	75,966										71,702
Issuance of common stock to Savings and Investment Plan					7,440						7,440
Share-based compensation expense					2,042						2,042
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					1,388
Proceeds from stock option exercises											1,388
Stock Redeemed or Called During Period, Value					(53)						(53)
Distributions to noncontrolling interests		(5,342)								(737)	(737)
Adjustments to redemption amount of redeemable noncontrolling interests		2,122							(2,122)		(2,122)
Adjustments to Additional Paid in Capital, Other					71						71
Ending Balance at Apr. 30, 2021			542	811	311,995	4,777	(4,777)	1,674	1,812,798	32,070	2,159,890
Starting Balance, Redeemable Noncontrolling Interests at Jan. 31, 2021		222,225
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	5,748	4,264								1,484
Distributions to noncontrolling interests		(5,342)								(737)	(737)
Adjustments to redemption amount of redeemable noncontrolling interests		2,122							(2,122)		(2,122)
Temporary Equity, Other Changes	(3)
Ending Balance, Redeemable Noncontrolling Interests at Apr. 30, 2021		223,266
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	149,929							(22,002)	171,931
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	14,440	9,262								5,178
Comprehensive income	164,369										155,107
Cash dividends									(12,227)		(12,227)
Issuance of common stock to Savings and Investment Plan					7,739						7,739
Share-based compensation expense					6,855						6,855
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					1,604
Proceeds from stock option exercises			3	3							1,610
Stock Redeemed or Called During Period, Value			(1)	(1)	(23,690)						(23,692)
Distributions to noncontrolling interests		(9,968)								(608)	(608)
Adjustments to redemption amount of redeemable noncontrolling interests		9,047							(9,047)		(9,047)
Adjustments to Additional Paid in Capital, Other					(2,202)						(2,202)
Ending Balance at Apr. 30, 2022	2,420,474		545	814	311,053	5,297	(5,297)	(30,554)	2,100,178	38,438	2,420,474
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	14,440	9,262								5,178
Noncontrolling Interest, Increase from Business Combination	39,235
Distributions to noncontrolling interests		(9,968)								(608)	(608)
Adjustments to redemption amount of redeemable noncontrolling interests		9,047							(9,047)		(9,047)
Temporary Equity, Other Changes	3,764
Ending Balance, Redeemable Noncontrolling Interests at Apr. 30, 2022	303,927	303,927
Beginning Balance at Jan. 31, 2022			545	814	302,104	5,297	(5,297)	(16,962)	2,018,990	36,565	2,342,056
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	71,418							(13,592)	85,010
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	7,439	5,121								2,318
Comprehensive income	78,857										73,736
Issuance of common stock to Savings and Investment Plan					6,069						6,069
Share-based compensation expense					3,241						3,241
Proceeds from stock option exercises, Adjustment to Additional Paid in Capital					841
Proceeds from stock option exercises											841
Stock Redeemed or Called During Period, Value					(69)						(69)
Distributions to noncontrolling interests		(4,085)								(445)	(445)
Adjustments to redemption amount of redeemable noncontrolling interests		3,822							(3,822)		(3,822)
Adjustments to Additional Paid in Capital, Other					(1,133)						(1,133)
Ending Balance at Apr. 30, 2022	2,420,474		$ 545	$ 814	$ 311,053	$ 5,297	$ (5,297)	$ (30,554)	2,100,178	38,438	2,420,474
Starting Balance, Redeemable Noncontrolling Interests at Jan. 31, 2022		258,289
Increase (Decrease) in Temporary Equity [Roll Forward]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	7,439	5,121								2,318
Noncontrolling Interest, Increase from Business Combination	39,063
Distributions to noncontrolling interests		(4,085)								$ (445)	(445)
Adjustments to redemption amount of redeemable noncontrolling interests		3,822							$ (3,822)		$ (3,822)
Temporary Equity, Other Changes	1,717
Ending Balance, Redeemable Noncontrolling Interests at Apr. 30, 2022	$ 303,927	$ 303,927