Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments (Details)

v2.4.1.9
Fair Value of Financial Instruments (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Securities Sold under Agreements to Repuchase, Long-term $ 98,289two_SecuritiesSoldUnderAgreementsToRepuchaseLongTerm $ 93,221two_SecuritiesSoldUnderAgreementsToRepuchaseLongTerm
Assets Sold under Agreements to Repurchase, Repurchase Liability 13,094,878us-gaap_AssetsSoldUnderAgreementsToRepurchaseRepurchaseLiability 12,932,463us-gaap_AssetsSoldUnderAgreementsToRepurchaseRepurchaseLiability
Long-term Federal Home Loan Bank Advances 2,625,000us-gaap_FederalHomeLoanBankAdvancesLongTerm  
Maturity Over One Year [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability $ 98,289us-gaap_AssetsSoldUnderAgreementsToRepurchaseRepurchaseLiability
/ us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis
= two_MaturityOverOneYearMember
$ 93,221us-gaap_AssetsSoldUnderAgreementsToRepurchaseRepurchaseLiability
/ us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis
= two_MaturityOverOneYearMember