SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	3 Months Ended
Mar. 31, 2024 item state
Number of full-service bank offices \| item	30
HarborOne Mortgage
Additional states licensed to lend \| state	5

Represents the number of additional states in which the entity is licensed to lend.

No definition available.

Name:	hone_AdditionalStatesLicensedToLend
Namespace Prefix:	hone_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration