Note 16 - Statutory Information Statutory Information (Details) (USD $)		12 Months Ended						12 Months Ended					12 Months Ended				12 Months Ended				1 Months Ended	12 Months Ended			55 Months Ended		12 Months Ended					3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012 Differences Between GAAP Basis and STAT Basis [Member] years	Dec. 31, 2012 Statutory Policyholder Surplus [Member] PENNSYLVANIA	Dec. 31, 2012 CMAC Of Texas [Member]	Dec. 31, 2011 CMAC Of Texas [Member]	Dec. 31, 2010 CMAC Of Texas [Member]	Dec. 31, 2013 CMAC Of Texas [Member]	Dec. 31, 2012 CMAC Of Texas [Member] Statutory Policyholder Surplus [Member] State and Local Jurisdiction [Member]	Dec. 31, 2012 Radian Mortgage Insurance [Member]	Dec. 31, 2011 Radian Mortgage Insurance [Member]	Dec. 31, 2010 Radian Mortgage Insurance [Member]	Dec. 31, 2013 Radian Mortgage Insurance [Member]	Dec. 31, 2012 Radian Insurance [Member]	Dec. 31, 2011 Radian Insurance [Member]	Dec. 31, 2010 Radian Insurance [Member]	Dec. 31, 2013 Radian Insurance [Member]	Dec. 31, 2012 Radian Mortgage Assurance [Member]	Dec. 31, 2011 Radian Mortgage Assurance [Member]	Dec. 31, 2010 Radian Mortgage Assurance [Member]	Dec. 31, 2013 Radian Mortgage Assurance [Member]	Jul. 31, 2012 Radian Guaranty [Member]	Dec. 31, 2012 Radian Guaranty [Member]	Dec. 31, 2011 Radian Guaranty [Member]	Dec. 31, 2010 Radian Guaranty [Member]	Dec. 31, 2012 Radian Guaranty [Member]	Dec. 31, 2013 Radian Guaranty [Member]	Dec. 31, 2012 Radian Asset Assurance [Member] derivative	Dec. 31, 2011 Radian Asset Assurance [Member]	Dec. 31, 2010 Radian Asset Assurance [Member]	Dec. 31, 2012 Radian Asset Assurance [Member] NEW YORK	Dec. 31, 2012 Radian Asset Assurance [Member] Statutory Policyholder Surplus [Member] NEW YORK	Sep. 30, 2013 Radian Asset Assurance [Member] Scenario, Forecast [Member]	Dec. 31, 2011 Radian Asset Assurance [Member] Adjusted Net Investment Income [Member] NEW YORK	Dec. 31, 2012 Radian Asset Assurance [Member] Municipal Bonds [Member] NEW YORK	Dec. 31, 2012 Radian Asset Assurance [Member] Non Investment Grade Obligations [Member] NEW YORK
Statutory Accounting Practices [Line Items]
Restricted Cash and Cash Equivalents	$ 1,200,000,000
Statutory Unassigned Negative Surplus									85,400,000	87,100,000			317,300,000	379,100,000			160,500,000	162,500,000				685,100,000	767,700,000		685,100,000
Statutory net (loss) income				16,000,000	(46,600,000)	(194,700,000)			1,700,000	(11,100,000)	(60,600,000)		58,000,000	4,300,000	43,900,000		2,000,000	(600,000)	7,400,000			(175,900,000)	(545,100,000)	(535,200,000)			103,300,000	69,100,000	58,000,000
Statutory policyholers' surplus				42,300,000	26,200,000	40,800,000			81,800,000	20,000,000	10,100,000		218,600,000	156,800,000	151,700,000		18,500,000	16,500,000	17,100,000			926,000,000	843,200,000	1,295,700,000	926,000,000		1,144,100,000	973,900,000	1,048,600,000
Statutory Salvage Recovery																											76,300,000
Number of Terminated TruPs CDO's That Have Risk of Default																											4
Statutory contingency reserve				0	0	0			0	0	0		20,600,000	0	1,500,000							0	0	19,600,000	0		300,100,000	421,400,000	392,600,000
Additional Risk And Capital Information
Capital Contributions						101,000,000			60,000,000
Claims Paying Resources																											1,800,000,000
Required statutory surplus				20,000,000					20,000,000				20,000,000				1,125,000										66,400,000
MInimum Statutory Surplus Committted To Be Maintained Each Quarter																	5,000,000
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries																					54,000,000				383,800,000		54,000,000	53,400,000	69,200,000			35,000,000
Statutory Minimum Policyholders' Surplus Required For Financial Guaranty Insurers In The State Of New York																											65,000,000
Statutory Minimum Policyholders' Surplus Required For Other Lines Of Insurance By The State Of New York																											1,400,000
Policyholder Dividends, Rate on Policy Earnings			10.00%					10.00%																							10.00%		100.00%
The Insured Average Annual Debt Service For A Single Risk, Net Of Reinsurance And Collateral, May Not Exceed This Percentage Of The Sum Of The Insurer's Policyholders' Surplus And Contingency Reserves																														10.00%
Insured Principal Of Municipal Bonds Attributable To Any Single Risk, Net Of Reinsurance And Collateral, Is Limited To This Percentage Of The Insurer's Policyholders' Surplus And Contingency Reserves																														75.00%
Aggregate Risk Limit for Financial Guarantee Insurance Contracts																																		0.33%	4.00%
STAT Accounting Information [Abstract]
Mortgage Guaranty Insurance Companies Are Required Each Year To Establish A Contingency Reserve Equal To This Percentage Of Premiums Earned In Such Year		50.00%
Number Of Years A Fifty Percent Contingency Reserve Is Required To Be Maintained		10
Mortgage Guaranty Insurance Companies Contingency Reserve May Be Reduced With Regulatory Approval To The Extent That Losses In Any Calendar Year Exceed This Percentage Of Earned Premiums For Such Year		35.00%
For Financial Guaranty Policies, Each Insurer Must Establish A Contingency Reserve Equal To The Greater Of This Percentage Of Premiums Written Or A Stated Percentage Of The Principal Guaranteed		50.00%
Range Of Years The Contingency Reserve Must Be Maintained, Low End		15
Range Of Years The Contingency Reserve Must Be Maintained, High End		20
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments							$ 0					$ 0				$ 0				$ 0						$ 0