CONDENSED CONSOLIDATED BALANCE SHEETS - UNAUDITED [PARENTHETICAL] - USD ($) shares in Thousands, $ in Thousands	Jan. 31, 2021	Oct. 31, 2020
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000	10,000
Preferred Stock, Shares Issued	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	150,000	150,000
Common stock, shares issued	54,195	54,195
Common stock, shares outstanding		54,195
Shareholders' equity:
Preferred Stock, $.01 par value per share; 10,000 shares authorized; none issued	$ 0	$ 0
Common Stock	542	542
Capital in excess of par value	301,107	299,930
Deferred compensation obligation	4,777	4,886
HEICO stock held by irrevocable trust	(4,777)	(4,886)
Accumulated other comprehensive loss	2,129	(9,149)
Retained earnings	$ 1,744,247	$ 1,688,045
Class A Common Stock [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	150,000	150,000
Common stock, shares issued	81,053	80,923
Common stock, shares outstanding	81,053	80,923
Shareholders' equity:
Common Stock	$ 811	$ 809