Name:	orc_GrossAmountOfRecognizedAssetsLiabilities
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

No definition available.

Name:	orc_GrossAmountOffsetInTheConsolidatedBalanceSheets
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Cash collateral not offset on the balance sheet of financial asset or liability or other contract elected not to be offset against an obligation to return collateral or right to receive collateral pledged under a master netting arrangement.

No definition available.

Name:	orc_GrossAmountsOfCashCollateralNotOffsetOnTheBalanceSheet
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Fair value of financial asset or liability or other contract elected not to be offset against an obligation to return collateral or right to receive collateral pledged under a master netting arrangement.

No definition available.

Name:	orc_GrossAmountsOfFinancialInstrumentsNotOffsetOnTheBalanceSheet
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Net amount after deducting gross amounts not offset on the balance sheet from net amount of assets (liabilities) presented on the balance sheet.

No definition available.

Name:	orc_NetAmountAfterDeductingGrossAmountsNotOffsetOnTheBalanceSheetFromNetAmountOfAssetsLiabilitiesPresentedOnTheBalanceSheet
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Fair value after effects of master netting arrangements, of a financial asset or liability or other contract and the contract can be net settled by means outside the contract or delivery of an asset or liability.

No definition available.

Name:	orc_NetAmountOfAssetsLiabilitiesPresentedOnTheBalanceSheet
Namespace Prefix:	orc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_AssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_DerivativeInstrumentRiskAxis=orc_PayerSwaptionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DerivativeInstrumentRiskAxis=orc_ReverseRepurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: