STOCK-BASED COMPENSATION, (Details) - shares	Sep. 30, 2021	Dec. 31, 2020
Dime 2020 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	1,123,639
Unvested and outstanding share-based awards		0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested and outstanding share-based awards	38,948,000	0
Sales Incentive Award Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested and outstanding share-based awards		0

Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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