GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
GOODWILL AND INTANGIBLE ASSETS
Change in goodwill	$ 0	$ 0
Goodwill	69,802	69,802	$ 69,802
Goodwill impairment	0
Intangible assets	2,082	2,272
HarborOne Mortgage
GOODWILL AND INTANGIBLE ASSETS
Goodwill	10,800	10,800
HarborOne Bank.
GOODWILL AND INTANGIBLE ASSETS
Goodwill	$ 59,000	$ 59,000

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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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of increase (decrease) 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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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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