XML 16 R25.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Repurchase Agreements Repurchase Agreements, Term to Original Maturity (Details) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | $ 3,055,069 | $ 3,013,110
Less than 30 days [Member] |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 602,224 | 250,635
30 to 90 days [Member] |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 2,224,106 | 617,399
91 to 180 days [Member] |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 178,242 | 904,830
181 to 364 days [Member] |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 0 | 1,030,569
1 year or longer [Member] |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | $ 50,497 | $ 209,677

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 No definition available. + Details
Name: | us-gaap_AssetsAndAssociatedLiabilitiesOfTransfersAccountedForAsSecuredBorrowingsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=34720971&loc=SL6224234-111729 + Details
Name: | us-gaap_TransfersAccountedForAsSecuredBorrowingsAssociatedLiabilitiesCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis=dx_Lessthan30daysMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis=dx_A30to90daysMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis=dx_A91to180daysMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis=dx_A6monthsto1yearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis=dx_A1yearorlongerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |