Business acquisition purchase price.

No definition available.

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Namespace Prefix:	dcom_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

+ Details

Name:	us-gaap_BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

+ Details

Name:	us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Data Type:	na
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- Details

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MERGER - Purchase Price (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Feb. 01, 2021	Jan. 31, 2021	Mar. 31, 2021
MERGER
Number of hypothetical Legacy Dime shares issued to Bridge shareholders		41,226,000
Number of Bridge Outstanding Shares		41,226,000
Cash in lieu of fractional shares		$ 1,007,140
Purchase price consideration			$ 491,210
Bridge shareholders
MERGER
Number of hypothetical Legacy Dime shares issued to Bridge shareholders	21.2	19,993,000
Number of Bridge Outstanding Shares	21.2	19,993,000
Cash in lieu of fractional shares		$ 488,420
Legacy Dime shareholders
MERGER
Number of hypothetical Legacy Dime shares issued to Bridge shareholders	30,853,000	21,233,000
Legacy Dime market price per share as of February 1, 2021	$ 15.90
Purchase price determination of hypothetical Legacy Dime shares issued to Bridge shareholders	$ 490,560
Number of Bridge Outstanding Shares	30,853,000	21,233,000
Cash in lieu of fractional shares	$ 7	$ 518,720
Purchase price consideration	$ 491,210
Legacy Dime shareholders \| Common Stock
MERGER
Number of hypothetical Legacy Dime shares issued to Bridge shareholders	643,000
Number of Bridge Outstanding Shares	643,000