Annual report pursuant to Section 13 and 15(d)

Derivative Instruments and Hedging Activities Schedule of TBA Contracts (Details)

v2.4.1.9
Derivative Instruments and Hedging Activities Schedule of TBA Contracts (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Derivative [Line Items]      
Derivative, Notional Amount $ (48,115,523)invest_DerivativeNotionalAmount $ (37,366,610)invest_DerivativeNotionalAmount $ (22,377,656)invest_DerivativeNotionalAmount
Derivative Financial Instruments, Assets [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (36,315,523)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
(30,383,908)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
 
Derivative, Fair Value, Net 380,791us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
549,859us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
 
Derivative Financial Instruments, Liabilities [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (16,200,000)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
(10,876,702)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
 
Derivative, Fair Value, Net (90,233)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
(22,081)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
 
Forward Contracts [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (1,325,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
(603,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
(953,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
Derivative, Cost (1,431,945)two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
790,392two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Derivative, Market Value (1,439,282)two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
823,693two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Forward Contracts [Member] | Long [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (875,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
(2,550,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Derivative, Cost 862,868two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
2,749,648two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Derivative, Market Value 873,218two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
2,767,295two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Forward Contracts [Member] | Short [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (2,200,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
(1,947,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
 
Derivative, Cost 2,294,813two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
1,959,256two_DerivativeCost
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
 
Derivative, Market Value 2,312,500two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
1,943,602two_DerivativeMarketValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Assets [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (875,000)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
(4,097,000)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Derivative, Fair Value, Net 10,350us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
33,425us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Assets [Member] | Long [Member]      
Derivative [Line Items]      
Derivative, Fair Value, Net 10,350us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
17,771us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Assets [Member] | Short [Member]      
Derivative [Line Items]      
Derivative, Fair Value, Net 0us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
15,654us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Liabilities [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (2,200,000)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
(400,000)invest_DerivativeNotionalAmount
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Derivative, Fair Value, Net (17,687)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
(125)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Liabilities [Member] | Long [Member]      
Derivative [Line Items]      
Derivative, Fair Value, Net 0us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
(125)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Forward Contracts [Member] | Derivative Financial Instruments, Liabilities [Member] | Short [Member]      
Derivative [Line Items]      
Derivative, Fair Value, Net (17,687)us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
0us-gaap_DerivativeFairValueOfDerivativeNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
 
Agency To-be-Announced Securities, Non-Risk Management [Member] | Long [Member]      
Derivative [Line Items]      
Derivative, Notional Amount   (2,150,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= two_AgencyTobeAnnouncedSecuritiesNonRiskManagementMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
 
Interest Rate Risk Associated with the Investment Portfolio [Member] | Forward Contracts [Member] | Long [Member]      
Derivative [Line Items]      
Derivative, Notional Amount (875,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
/ two_RiskTypeAxis
= two_InterestRateRiskAssociatedwiththeInvestmentPortfolioMember
(400,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_LongMember
/ two_RiskTypeAxis
= two_InterestRateRiskAssociatedwiththeInvestmentPortfolioMember
 
Interest Rate Risk Associated with the Investment Portfolio [Member] | Forward Contracts [Member] | Short [Member]      
Derivative [Line Items]      
Derivative, Notional Amount $ (2,200,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
/ two_RiskTypeAxis
= two_InterestRateRiskAssociatedwiththeInvestmentPortfolioMember
$ (1,947,000)invest_DerivativeNotionalAmount
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForwardContractsMember
/ us-gaap_PositionAxis
= us-gaap_ShortMember
/ two_RiskTypeAxis
= two_InterestRateRiskAssociatedwiththeInvestmentPortfolioMember