XML 61 R42.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Derivatives - Schedule of Interest Rate Hedging Instruments (Details) - USD ($) | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Derivative [Line Items] |  |
Derivative assets | $ 133,000 | $ 54,361,000
Derivative liabilities | 22,814,000 | 0
U.S. Treasury futures |  |
Derivative [Line Items] |  |
Derivative assets | 1,900,000 |
Derivative Instruments Not Designated as Hedging Instruments, at Carrying Value | 0 |
Derivative liabilities |  | 219,900,000
U.S. Treasury futures | Short position | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | (1,251,500,000) | (4,880,000,000)
Interest rate swaps |  |
Derivative [Line Items] |  |
Derivative assets | 152,800,000 |
Derivative Instruments Not Designated as Hedging Instruments, at Carrying Value | 0 |
Derivative liabilities |  | 0
Interest rate swaps | Short position | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | $ (5,385,000,000) | $ 0
Derivative, Average Fixed Interest Rate | 3.61% |
Interest rate swaps | Short position | Not Designated as Hedging Instrument, Economic Hedge | Less than 5 years |  |
Derivative [Line Items] |  |
Notional balance | $ (1,275,000,000) |
Derivative, Average Fixed Interest Rate | 3.42% |
Interest rate swaps | Short position | Not Designated as Hedging Instrument, Economic Hedge | Less than 7 years |  |
Derivative [Line Items] |  |
Notional balance | $ (3,085,000,000) |
Derivative, Average Fixed Interest Rate | 3.61% |
Interest rate swaps | Short position | Not Designated as Hedging Instrument, Economic Hedge | 9-10 years |  |
Derivative [Line Items] |  |
Notional balance | $ (1,025,000,000) |
Derivative, Average Fixed Interest Rate | 3.83% |

X
- Definition Derivative Instruments Not Designated as Hedging Instruments, Carrying Value + References No definition available. + Details
Name: | dx_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsCarryingValue
Namespace Prefix: | dx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Average fixed interest rate related to the group of interest rate derivatives. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B + Details
Name: | us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B + Details
Name: | us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_FutureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PositionAxis=us-gaap_ShortMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dx_MaturityInformationAxis=dx_LessThan5YearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dx_MaturityInformationAxis=dx_A67YearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dx_MaturityInformationAxis=dx_A910YearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |