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DEPOSITS - Narrative (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Feb. 01, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Time Deposits [Line Items] |  |  |
Deposits acquired |  | $ 5,410.0 |
$250,000 or Greater |  |  |
Time Deposits [Line Items] |  |  |
Deposits in excess of the FDIC limit | $ 200.1 |  | $ 279.0

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- Definition The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $250,000 or more. + References No definition available. + Details
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Namespace Prefix: | dcom_
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Period Type: | instant

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- Definition The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123413009&loc=d3e4845-128472 + Details
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- References No definition available. + Details
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- Details
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Namespace Prefix: |
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Period Type: |