XML 34 R76.htm IDEA: XBRL DOCUMENT v2.4.1.9
Note 11 - Long-Term Debt Schedule of Long Term Debt (Details) (USD $)
12 Months Ended 8 Months Ended 2 Months Ended 10 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2014
basispoint
Dec. 31, 2010
Dec. 31, 2013
Jun. 30, 2005
Jun. 01, 2005
Nov. 30, 2010
Mar. 31, 2013
May 31, 2014
Nov. 15, 2010
Debt Instrument [Line Items]                        
Long-term debt $ 1,209,926,000us-gaap_LongTermDebt $ 930,072,000us-gaap_LongTermDebt   $ 1,209,926,000us-gaap_LongTermDebt   $ 930,072,000us-gaap_LongTermDebt            
Repayments of Long-term Debt 57,223,000us-gaap_RepaymentsOfLongTermDebt 79,372,000us-gaap_RepaymentsOfLongTermDebt 153,261,000us-gaap_RepaymentsOfLongTermDebt                  
Senior Notes Due 2015                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage             5.375%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
         
Long-term debt 0us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
54,481,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
  0us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
  54,481,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
           
Debt Instrument, Face Amount               250,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
       
Gains (Losses) on Extinguishment of Debt (2,800,000)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
                     
Repayments of Long-term Debt 57,200,000us-gaap_RepaymentsOfLongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
                     
Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage   9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
      9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
           
Long-term debt 192,605,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
191,611,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
  192,605,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
  191,611,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
           
Convertible Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage                 3.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
     
Long-term debt 375,310,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
[1] 353,798,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
[1]   375,310,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
[1]   353,798,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
[1]            
Convertible Senior Notes Due 2019                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage                   2.25%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
   
Long-term debt 342,011,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
[2] 330,182,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
[2]   342,011,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
[2]   330,182,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
[2]            
Senior Notes Due 2019 [Member]                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage                     5.50%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
 
Long-term debt 300,000,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
0us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
  300,000,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
  0us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
           
Debt Instrument, Face Amount                     300,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
 
Proceeds from Issuance of Long-term Debt       293,800,000us-gaap_ProceedsFromIssuanceOfLongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
               
Debt Instrument, Redemption Price, Percentage       100.00%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
               
Number of Basis Points Added to Treasury Rate Used in Calculating Redemption Price of Debt 50rdn_NumberofBasisPointsAddedtoTreasuryRateUsedinCalculatingRedemptionPriceofDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
    50rdn_NumberofBasisPointsAddedtoTreasuryRateUsedinCalculatingRedemptionPriceofDebt
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2019Member
               
Total Long Term Debt                        
Debt Instrument [Line Items]                        
Long-term debt 1,209,926,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_TotalLongTermDebtMember
930,072,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_TotalLongTermDebtMember
  1,209,926,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_TotalLongTermDebtMember
  930,072,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_TotalLongTermDebtMember
           
Senior Notes [Member]                        
Debt Instrument [Line Items]                        
Percent of Stock With Ordinary Voting Rights That the Company Must Retain In Order to Make Any Capital Stock Transactions Under Debt Covenant Agreement 80.00%rdn_PercentOfStockWithOrdinaryVotingRightsThatCompanyMustRetainInOrderToMakeAnyCapitalStockTransactionsUnderDebtCovenantAgreement
/ us-gaap_DebtInstrumentAxis
= us-gaap_SeniorNotesMember
    80.00%rdn_PercentOfStockWithOrdinaryVotingRightsThatCompanyMustRetainInOrderToMakeAnyCapitalStockTransactionsUnderDebtCovenantAgreement
/ us-gaap_DebtInstrumentAxis
= us-gaap_SeniorNotesMember
               
Convertible Debt [Member] | Convertible Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage                 3.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
     
Long-term debt 375,310,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
353,798,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  375,310,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  353,798,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
           
Long-term Debt, Gross 450,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
450,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  450,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  450,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
           
Debt Instrument, Face Amount                       450,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
Proceeds from Issuance of Long-term Debt         391,300,000us-gaap_ProceedsFromIssuanceOfLongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
             
Debt Instrument, Interest Rate, Effective Percentage                 9.75%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
     
Debt Instrument, Convertible, Conversion Ratio 85.5688us-gaap_DebtInstrumentConvertibleConversionRatio1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Conversion, Converted Instrument, Amount 1,000us-gaap_DebtConversionConvertedInstrumentAmount1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Conversion Price $ 11.69us-gaap_DebtInstrumentConvertibleConversionPrice1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
    $ 11.69us-gaap_DebtInstrumentConvertibleConversionPrice1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
               
Common Stock, Capital Shares Reserved for Future Issuance 51,000,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
    51,000,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
               
Maximum Stock Price Per Share Included In Capped Call Transaction $ 14.11rdn_MaximumStockPricePerShareIncludedInCappedCallTransaction
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
    $ 14.11rdn_MaximumStockPricePerShareIncludedInCappedCallTransaction
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
               
Cash Paid To Purchase Capped Call Transactions                       46,100,000rdn_CashPaidToPurchaseCappedCallTransactions
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
Convertible Debt [Member] | Convertible Senior Notes Due 2019                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage                   2.25%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
   
Long-term debt 342,011,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
330,182,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  342,011,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  330,182,000us-gaap_LongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
           
Long-term Debt, Gross 400,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
400,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  400,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
  400,000,000us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
           
Debt Instrument, Face Amount                   400,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
   
Proceeds from Issuance of Long-term Debt           389,800,000us-gaap_ProceedsFromIssuanceOfLongTermDebt
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
           
Debt Instrument, Interest Rate, Effective Percentage                   6.25%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
   
Debt Instrument, Convertible, Conversion Ratio 94.3396us-gaap_DebtInstrumentConvertibleConversionRatio1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Conversion, Converted Instrument, Amount 1,000us-gaap_DebtConversionConvertedInstrumentAmount1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Conversion Price $ 10.60us-gaap_DebtInstrumentConvertibleConversionPrice1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
    $ 10.60us-gaap_DebtInstrumentConvertibleConversionPrice1
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
               
Common Stock, Capital Shares Reserved for Future Issuance 50,000,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
    50,000,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
               
Redemption Trigger based on Company Stock Price [Member] | Convertible Debt [Member] | Convertible Senior Notes Due 2019                        
Debt Instrument [Line Items]                        
Debt Instrument, Convertible, Threshold Trading Days 20us-gaap_DebtInstrumentConvertibleThresholdTradingDays
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_RedemptionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Threshold Consecutive Trading Days 30 days                      
Debt Instrument, Convertible, Stock Price Trigger, Percent 130.00%rdn_DebtInstrumentConvertibleStockPriceTriggerPercent
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_RedemptionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Redemption Price, Percentage 100.00%rdn_DebtInstrumentConvertibleRedemptionPricePercentage
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_RedemptionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Conversion Trigger based on Company Stock Price [Member] | Convertible Debt [Member] | Convertible Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Convertible, Threshold Trading Days 20us-gaap_DebtInstrumentConvertibleThresholdTradingDays
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Threshold Consecutive Trading Days 30 days                      
Debt Instrument, Convertible, Stock Price Trigger, Percent 130.00%rdn_DebtInstrumentConvertibleStockPriceTriggerPercent
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Conversion Trigger based on Company Stock Price [Member] | Convertible Debt [Member] | Convertible Senior Notes Due 2019                        
Debt Instrument [Line Items]                        
Debt Instrument, Convertible, Threshold Trading Days 20us-gaap_DebtInstrumentConvertibleThresholdTradingDays
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Threshold Consecutive Trading Days 30 days                      
Debt Instrument, Convertible, Stock Price Trigger, Percent 130.00%rdn_DebtInstrumentConvertibleStockPriceTriggerPercent
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Conversion Trigger based on Trading Price of Debt Versus Company Stock Price [Member] | Convertible Debt [Member] | Convertible Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Convertible, Threshold Trading Days 5us-gaap_DebtInstrumentConvertibleThresholdTradingDays
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnTradingPriceOfDebtVersusCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Threshold Consecutive Trading Days 5 days                      
Debt Instrument, Convertible, Debt Price Trigger, Percent 98.00%rdn_DebtInstrumentConvertibleDebtPriceTriggerPercent
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnTradingPriceOfDebtVersusCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Conversion Trigger based on Trading Price of Debt Versus Company Stock Price [Member] | Convertible Debt [Member] | Convertible Senior Notes Due 2019                        
Debt Instrument [Line Items]                        
Debt Instrument, Convertible, Threshold Trading Days 5us-gaap_DebtInstrumentConvertibleThresholdTradingDays
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnTradingPriceOfDebtVersusCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Instrument, Convertible, Threshold Consecutive Trading Days 5 days                      
Debt Instrument, Convertible, Debt Price Trigger, Percent 98.00%rdn_DebtInstrumentConvertibleDebtPriceTriggerPercent
/ us-gaap_DebtConversionByUniqueDescriptionAxis
= rdn_ConversionTriggerBasedOnTradingPriceOfDebtVersusCompanyStockPriceMember
/ us-gaap_DebtInstrumentAxis
= rdn_ConvertibleSeniorNotesDue2019Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_ConvertibleDebtMember
                     
Debt Due 2015 Exchange | Senior Notes Due 2015                        
Debt Instrument [Line Items]                        
Extinguishment of Debt, Amount   195,500,000us-gaap_ExtinguishmentOfDebtAmount
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2015Member
                   
Debt Due 2015 Exchange | Senior Notes Due 2017                        
Debt Instrument [Line Items]                        
Debt Instrument, Interest Rate, Stated Percentage   9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
      9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
           
Debt Instrument, Face Amount 195,500,000us-gaap_DebtInstrumentFaceAmount
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
    195,500,000us-gaap_DebtInstrumentFaceAmount
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
               
Gains (Losses) on Extinguishment of Debt   $ (4,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ rdn_CapitalAndLiquidityAxis
= rdn_DebtDue2015ExchangeMember
/ us-gaap_DebtInstrumentAxis
= rdn_SeniorNotesDue2017Member
                   
[1] The principal amount of these notes is $450 million.
[2] The principal amount of these notes is $400 million.