Note 7 - Reinsurance (Details) (USD $)	3 Months Ended		6 Months Ended			3 Months Ended	6 Months Ended				6 Months Ended			6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Jun. 30, 2012 Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Smart Home [Member]	Jun. 30, 2012 Radian Guaranty [Member] Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Radian Guaranty [Member] Maximum [Member] Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Radian Guaranty [Member] Scenario, Forecast [Member] Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Radian Guaranty [Member] Scenario, Forecast [Member] Maximum [Member] Quota Share Reinsurance Agreement [Member]	Apr. 02, 2012 Radian Guaranty [Member] Scenario, Forecast [Member] Maximum [Member] Quota Share Reinsurance Agreement [Member]	Jun. 30, 2012 Radian Guaranty [Member] Scenario, Forecast [Member] Minimum [Member] Quota Share Reinsurance Agreement [Member]	Apr. 02, 2012 Radian Guaranty [Member] Scenario, Forecast [Member] Minimum [Member] Quota Share Reinsurance Agreement [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded Credit Risk, Unearned Premiums	$ 22,700,000		$ 22,700,000		$ 800,000
Reinsurance recoverables	103,143,000		103,143,000		157,985,000
Direct Premiums Written	214,349,000	174,008,000	418,102,000	364,849,000
Assumed Premiums Written	(1,028,000)	(11,788,000)	(88,516,000)	(10,164,000)
Ceded Premiums Written	(31,389,000)	(9,442,000)	(69,976,000)	(19,158,000)		(25,500,000)	(25,500,000)
Net premiums written	181,932,000	152,778,000	259,610,000	335,527,000
Reinsurance Premiums for Insurance Companies, by Product Segment, Gross Amount	196,012,000	186,640,000	388,028,000	391,098,000
Reinsurance Premiums for Insurance Companies, by Product Segment, Amount Assumed from Other Companies	1,704,000	12,064,000	(8,981,000)	20,694,000
Reinsurance Premiums for Insurance Companies, by Product Segment, Amount Ceded to Other Companies	(10,937,000)	(9,770,000)	(24,903,000)	(19,835,000)		(3,100,000)	(3,100,000)
Fees and Commissions						6,400,000	6,400,000
Net premiums earned-insurance	186,779,000	188,934,000	354,144,000	391,957,000
Percentage of New Insurance Written To Be Ceded Pursuant To The April 2012 Quota Share Reinsurance Agreement											20.00%
First Lien Primary Mortgage Insurance Risk In Force									922,500,000				1,600,000,000		1,250,000,000
Impact To Statutory Capital And Surplus												$ 62,500,000		$ 50,000,000
Percentage of Reinsurance Able To Be Commuted										66.66%
Number of Transactions Terminated								1