SELECTED FINANCIAL STATEMENT INFORMATION (Details Textuals) - USD ($) $ in Thousands	3 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Oct. 31, 2021
Selected Financial Statement Information (Details) [Abstract]
Accrued customer rebates and credits	$ 14,700		$ 13,200
Total customer rebates and credits deducted within net sales	$ 1,700	$ 800

Carrying value as of the balance sheet date of accrued customer rebates and credits.

No definition available.

Name:	hei_AccruedCustomerRebatesAndCredits
Namespace Prefix:	hei_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant