Note 14 - Statutory Information Statutory Information (Details) (USD $)	6 Months Ended	12 Months Ended	1 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2012 Radian Guaranty [Member]	Dec. 31, 2011 Radian Guaranty [Member]	Jul. 31, 2012 Radian Asset Assurance [Member]	Jun. 30, 2012 Radian Asset Assurance [Member]	Jun. 30, 2012 Radian Asset Assurance [Member] Terminated TruPs Bonds [Member]	Jun. 30, 2012 CMAC Of Texas [Member]	Jun. 30, 2012 Scenario, Forecast [Member] Radian Asset Assurance [Member]
Statutory Accounting Practices [Line Items]
Statutory net loss	$ (120,200,000)	$ (545,100,000)				$ 18,100,000
Statutory surplus	923,500,000	843,200,000		1,200,000,000		44,400,000
Additional Risk And Capital Information
Claims Paying Resources				1,800,000,000
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries			54,000,000	54,000,000			40,000,000
Required statutory surplus						20,000,000
Current Transactions [Abstract]
Statutory Gain (Loss) on Contract Termination					$ 7,000,000