Annual report pursuant to Section 13 and 15(d)

Available-for-Sale Securities, at Fair Value Other than Temporary Impairment, Credit Losses Recognized in Earnings (Details)

v2.4.1.9
Available-for-Sale Securities, at Fair Value Other than Temporary Impairment, Credit Losses Recognized in Earnings (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]                      
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Available-for-sale Securities $ (180)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ 0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ 0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (212)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ 0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ 0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (1,426)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (236)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (392)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (1,662)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities $ (10,952)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities
Other than Temporary Impairment Losses, Investments, Number, Available-for-sale Securities                 3two_OtherThanTemporaryImpairmentLossesInvestmentsNumberAvailableForSaleSecurities 4two_OtherThanTemporaryImpairmentLossesInvestmentsNumberAvailableForSaleSecurities 33two_OtherThanTemporaryImpairmentLossesInvestmentsNumberAvailableForSaleSecurities
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Market Value 161,134two_OtherthanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecuritiesMarketValue               161,134two_OtherthanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecuritiesMarketValue    
Available-for-sale Securities, Weighted Average Cumulative Losses 10.90%two_AvailableForSaleSecuritiesWeightedAverageCumulativeLosses               10.90%two_AvailableForSaleSecuritiesWeightedAverageCumulativeLosses    
Available-for-sale Securities, Weighted Average Three-Month Prepayment Speed 0.037two_AvailableForSaleSecuritiesWeightedAverageThreeMonthPrepaymentSpeed               0.037two_AvailableForSaleSecuritiesWeightedAverageThreeMonthPrepaymentSpeed    
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures, Delinquency Rate                 29.70%us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecuritiesPortionRecognizedInEarningsNetQualitativeDisclosuresDelinquencyRate    
Available-for-sale Securities, Weighted Average FICO Score 664two_AvailableForSaleSecuritiesWeightedAverageFicoScore               664two_AvailableForSaleSecuritiesWeightedAverageFicoScore    
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held, Beginning Balance       (9,467)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld       (15,561)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld (9,467)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld (15,561)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld (5,102)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment                 (91)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment 0us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment (9,537)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses                 (301)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses (1,662)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses (1,415)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Cash Flows                 464us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows 1,677us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows 250us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Securities Sold                 1,154us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold 6,079us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold 243us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held, Ending Balance $ (8,241)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld       $ (9,467)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld       $ (8,241)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld $ (9,467)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld $ (15,561)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld