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FHLBNY ADVANCES - Narrative (Details) - USD ($) | Sep. 30, 2022 | Dec. 31, 2021
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FHLBNY ADVANCES [Abstract] |  |
Borrowings total | $ 620,000,000.0 | $ 25,000,000.0
Average interest rate on outstanding FHLBNY | 3.19% | 0.35%
Borrowings | $ 3,870,000,000 | $ 4,190,000,000
Callable advances | 0 |
FHLBNY advances with an overnight contractual maturity | 270,000,000.0 | 0
FHLBNY advances with contractual maturities after 2022 | $ 0 | $ 0

X
- Definition Amount of overnight borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages. + References No definition available. + Details
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X
- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year after year one. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References No definition available. + Details
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X
- Definition Maximum amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions. + References No definition available. + Details
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Namespace Prefix: | dcom_
Data Type: | xbrli:monetaryItemType
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X
- Definition Amount of federal home loan bank callable advances. + References No definition available. + Details
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Balance Type: | credit
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- References No definition available. + Details
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- Definition Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions. + References No definition available. + Details
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X
- Definition Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank). + References No definition available. + Details
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