Name:	dx_AmountOutstandingWithCounterparty
Namespace Prefix:	dx_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

Assets Sold Under Agreements to Repurchase, Number of Agreement Borrowings Available

No definition available.

Name:	dx_AssetsSoldUnderAgreementsToRepurchaseNumberOfAgreementBorrowingsAvailable
Namespace Prefix:	dx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Number of Agreement Borrowings Outstanding held by the entity.

No definition available.

Name:	dx_AssetsSoldUnderAgreementsToRepurchaseNumberOfAgreementBorrowingsOutstanding
Namespace Prefix:	dx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	dx_CounterpartyInformationLineItems
Namespace Prefix:	dx_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of equity at risk under all repurchase agreements with a particular counterparty where equity at risk is defined as the excess of carrying amount (or market value, if higher than the carrying amount) of the securities or other assets pledged as collateral to secure the repurchase agreement borrowings over the amount of the repurchase liability outstanding.

No definition available.

Name:	dx_RepurchaseAgreementCounterpartyPercentOfEquityAtRisk
Namespace Prefix:	dx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Weighted average interest rate on all amounts outstanding with a particular counterparty for whom the amount of equity at risk exceeds 10% of the Company's shareholder's equity.

No definition available.