Note 1 - Condensed Consolidated Financial Statements - Basis of Presentation and Business Overview Capital and Liquidity (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	6 Months Ended		1 Months Ended		1 Months Ended		73 Months Ended					1 Months Ended		1 Months Ended				6 Months Ended
	Jun. 30, 2014 segment	Jun. 30, 2013	May 31, 2014 Senior Notes Due 2019 [Member]	Jun. 30, 2014 Senior Notes Due 2019 [Member]	Jun. 30, 2014 Senior Notes Due 2015	Jun. 30, 2014 Mortgage Insurance Segment	Jun. 30, 2014 Radian Asset Assurance [Member]	Dec. 31, 2013 Radian Asset Assurance [Member]	Jun. 30, 2014 Parent Company	Jun. 30, 2014 Minimum [Member]	Jun. 30, 2014 Maximum [Member]	Jul. 31, 2014 Dividend Payment Made [Member] Radian Asset Assurance [Member]	Jun. 30, 2014 Less Than [Member] Mortgage Insurance Segment	May 31, 2014 Common Stock	Jun. 30, 2014 State Insurance Regulations [Member] Mortgage Insurance Segment state	Jun. 30, 2014 Non RBC States [Member] Minimum [Member]	Jun. 30, 2014 Non RBC States [Member] Maximum [Member]	Jun. 30, 2014 Primary Mortgage Product [Member] Mortgage Insurance Segment
Basis of Presentation and Business Overview [Line Items]
Equity Method Investment, Ownership Percentage										20.00%	50.00%
Business Overview [Abstract]
Number of Operating Segments	3
Mortgage Insurance [Abstract]
Private Mortgage Insurance Protects Lenders For Loans Made With This Maximum Downpayment Percentage						20.00%
Percentage Of Primary Insurance On Domestic First-Lien Mortgages To Total Risk In Force						96.20%
First Lien Primary Mortgage Insurance Risk In Force						$ 42,900,000,000
Percentage Of Pool Insurance On Domestic First-Lien Mortgages To Total Risk In Force						3.60%
NonTraditional Risk In Force						86,000,000
Percentage Of Non-Traditional RIF To Total RIF													1.00%
Business Conditions [Abstract]
Percentage of Legacy Portfolio Risk in Force to Total Risk in Force						35.00%
Percentage of Portfolio Risk in Force Originated Since 2009 to Total Risk in Force						65.00%
Percentage Decrease In New Defaults																		20.00%
Maximum Loan To Value Percentage For G.S.E. Acquired Loans						80.00%
Minimum Percentage Of The Loans In Excess Of An 80% L.T.V. Which Must Be Retained By The Mortgage Originator Or Seller						10.00%
Number of Days Until Eligibility Requirements Become Effective After Final Publication	180 days
Transition Period for Compliance to New Eligibility Requirements	2 years
Number Of States That Have A Statutory Or Regulatory Risk Based Capital Requirement															16
Risk To Capital Ratio, Regulatory Maximum	25
Capital Required for Capital Adequacy																1,000,000	5,000,000
Capital and Liquidity
Percentage Reduction Of Net Par Outstanding							82.00%
Net Par Outstanding							20,200,000,000
Statutory surplus							1,186,100,000	1,198,000,000
Cash Dividends Paid to Parent Company												150,000,000
Debt Instrument, Face Amount			300,000,000
Debt Instrument, Interest Rate, Stated Percentage			5.50%	5.50%	5.375%
Proceeds from Issuance of Debt			294,400,000
Common Stock, Shares, Issued														17,825
Sale of Stock, Price Per Share														$ 14.50
Issuance of common stock	247,388,000	299,542,000												247,388,000
Repayments of Long-term Debt	57,223,000	79,372,000			57,200,000
Gains (Losses) on Extinguishment of Debt					(2,800,000)
Unrestricted Cash And Liquid Investments Including Activity After The Balance Sheet Date									$ 790,000,000