Note 14 - Statutory Information Risk To Capital Calculation (Details) $ in Millions		12 Months Ended
		Dec. 31, 2015 USD ($) state	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Risk to Capital Line Items [Line Items]
Risk To Capital Ratio, Regulatory Maximum		25
Risk-to-capital		14.6	20.3
Surplus Note, Redemption Percentage		50.00%
Surplus Note, Amount Used in Calculation of Additional Redemption Allowed		$ 150.0
Radian Insurance [Member]
Risk to Capital Line Items [Line Items]
Risk In Force		48.5
Radian Guaranty [Member]
Risk to Capital Line Items [Line Items]
Proceeds from Contributions from Parent		100.0	$ 100.0	$ 230.4
Surplus Notes		325.0
Risk In Force	[1]	36,396.1	30,615.7
Statutory Accounting Practices, Statutory Capital and Surplus, Balance		1,686.5	1,325.2	1,317.8
Contingency reserve		860.9	389.4	$ 23.0
Statutory Accounting Practices, Statutory Policyholders' Surplus, Balance		$ 2,547.4	$ 1,714.6
Risk-to-capital		14.3	17.9
Parent Company
Risk to Capital Line Items [Line Items]
Related Party Transaction, Rate		0.00%
State Insurance Regulations [Member]
Risk to Capital Line Items [Line Items]
Number Of States That Have A Statutory Or Regulatory Risk Based Capital Requirement | state		16
Minimum [Member] | Non RBC States [Member]
Risk to Capital Line Items [Line Items]
Capital Required for Capital Adequacy		$ 1.0
Maximum [Member] | Non RBC States [Member]
Risk to Capital Line Items [Line Items]
Capital Required for Capital Adequacy		$ 5.0

[1] Excludes risk ceded through reinsurance contracts (to third parties and affiliates) and RIF on defaulted loans.