Note 13 - Statutory Information Statutory Information (Details) (USD $)		3 Months Ended	12 Months Ended	1 Months Ended	3 Months Ended	12 Months Ended	70 Months Ended	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2014 Radian Guaranty [Member]	Dec. 31, 2013 Radian Guaranty [Member]	Jul. 31, 2013 Radian Asset Assurance [Member]	Mar. 31, 2014 Radian Asset Assurance [Member]	Dec. 31, 2013 Radian Asset Assurance [Member]	Mar. 31, 2014 Radian Asset Assurance [Member]	Mar. 31, 2014 Radian Asset Assurance [Member] NEW YORK	Sep. 30, 2014 Radian Asset Assurance [Member] Scenario, Forecast [Member]
Statutory Accounting Practices [Line Items]
Restricted Net Assets Held by Consolidated Subsidiaries	$ 1,600,000,000
Statutory Accounting Practices, Statutory Net Income Amount		68,200,000	(23,800,000)		2,100,000	(24,900,000)
Statutory surplus		1,305,500,000	1,317,800,000		1,186,300,000	1,198,000,000	1,186,300,000
Statutory contingency reserve		108,200,000	23,000,000		271,800,000	264,000,000	271,800,000
Statutory Accounting Practices, Percent of Statutory Surplus to Policyholders Available for Dividend Payments without Regulatory Approval								10.00%
Statutory Accounting Practices, Percent of Statutory Adjusted Net Investment Income Available for Dividend Payments without Regulatory Approval								100.00%
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries				36,000,000					32,000,000
Claims Paying Resources					1,600,000,000		1,600,000,000
Percentage Reduction Of Net Par Outstanding							80.00%
Net Par Outstanding					22,700,000,000		22,700,000,000
Statutory Minimum Policyholders' Surplus Required For Financial Guaranty Insurers In The State Of New York					65,000,000		65,000,000
Statutory Minimum Policyholders' Surplus Required For Other Lines Of Insurance By The State Of New York					1,400,000		1,400,000
Statutory Accounting Practices, Statutory Capital and Surplus Required					$ 66,400,000		$ 66,400,000