Note 4 - Derivative Instruments Fair Values Derivatives, Balance Sheet Location by Derivative Contract Type (Details) (USD $)	Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2009
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 17,212,000		$ 26,212,000
Derivative liabilities	126,006,000		723,579,000	238,697,000
Financial Guaranty Credit Derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	15,400,000		14,500,000
Derivative liabilities	106,500,000		704,400,000
Financial Guaranty VIE Derivative Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	19,500,000		19,200,000
Derivative liabilities, net	(19,500,000)	[1]
Net Interest Margin Securities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	1,600,000		10,900,000
Other Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	200,000		800,000
Radian Group Consolidated [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	17,200,000		26,200,000
Derivative liabilities	126,000,000		723,600,000
Derivative liabilities, net	$ (108,800,000)		$ (697,400,000)

[1] Represents the fair value of an interest rate swap included in the consolidation of one of our financial guaranty transactions. The notional amount of the interest rate swap does not represent additional par exposure, and therefore, is excluded from this table. See Note 5 for information on our maximum exposure to loss from our consolidated financial guaranty transactions.