Note 15 - Statutory Information Risk To Capital Calculation (Details) (Radian Guaranty [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Radian Guaranty [Member]
Statutory Accounting Practices [Line Items]
Risk In Force	$ 18,095.7	[1]	$ 22,177.7	[1]
Statutory policyholers' surplus	843.2		1,295.7
Contingency Reserve	0		19.6
Statutory policyholders' position	$ 843.2		$ 1,315.3
Risk To Capital Ratio	21.5		16.8

[1] Risk in force is net of risk ceded through reinsurance contracts and also excludes risk in force on defaulted loans.