Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
GOODWILL AND INTANGIBLE ASSETS
Goodwill	$ 69,802	$ 69,802	$ 69,802
Intangible assets	2,461	$ 3,164
HarborOne Bank
GOODWILL AND INTANGIBLE ASSETS
Goodwill	59,000
HarborOne Mortgage.
GOODWILL AND INTANGIBLE ASSETS
Goodwill	$ 10,800