XML 81 R98.htm IDEA: XBRL DOCUMENT v2.4.1.9
Note 15 - Share-Based and Other Compensation Plans (Employee Stock Purchase Plan) (Details) (Employee Stock Purchase Plan [Member], Employee Stock Purchase Plan [Member], Equity Settled [Member])
6 Months Ended 12 Months Ended
Dec. 31, 2014
Jun. 30, 2014
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Employee Stock Purchase Plan [Member] | Employee Stock Purchase Plan [Member] | Equity Settled [Member]
         
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares of common stock authorized for issuance 2,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
  2,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
   
Shares sold to employees under ESPP Plans     67,743us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
95,287us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
204,834us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date     15.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPricePurchaseDate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
   
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]          
Expected life (months) 6 months 6 months      
Risk-free interest rate 0.32%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
0.34%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
     
Volatility 36.69%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
46.99%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
     
Dividend yield 0.03%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember
0.04%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockMember
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardPlanNameAxis
= rdn_EmployeeStockPurchasePlan2008Member
/ rdn_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementTypeAxis
= rdn_EquitySettledMember