Note 10 - Losses and LAE Rescissions And Denials (Details) - USD ($) $ in Thousands	Aug. 29, 2017	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Rescissions And Denials [Line Items]
Reserve for losses and loss adjustment expense (“LAE”) (Note 10)		$ 848,379	$ 976,399
2013 Freddie Mac Agreement [Member]
Rescissions And Denials [Line Items]
Reserve for losses and loss adjustment expense (“LAE”) (Note 10)		57,000
2013 Freddie Mac Agreement [Member] | Radian Guaranty Inc [Member]
Rescissions And Denials [Line Items]
Restricted Investments Held as Collateral for Master Transaction Agreement, Net		75,400	74,700
2013 Freddie Mac Agreement [Member] | Radian Guaranty Inc [Member] | Maximum [Member] | Scenario, Forecast [Member]
Rescissions And Denials [Line Items]
Not Final Loss Mitigation Activity	$ 74,000
Mortgage Insurance Segment
Rescissions And Denials [Line Items]
Decrease To Our Loss Reserves Due To Estimated Rescissions And Denials		65,000	69,000
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount		18,500	26,600
Reserve for losses and loss adjustment expense (“LAE”) (Note 10)		$ 848,379	$ 976,399	$ 1,204,792	$ 1,560,032