Note 18 - Statutory Information Statutory Dividend Restrictions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Net Assets Held by Consolidated Subsidiaries	$ 4,200,000
Radian Guaranty
Statutory Unassigned Negative Surplus	503,300
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments	0
Statutory Accounting Practices, Statutory Capital and Surplus, Additions	0	$ 0	$ 100,000
Statutory Accounting Practices, Statutory Capital and Surplus, Distributions	(375,000)	(450,000)	(175,000)
Radian Reinsurance
Statutory Unassigned Negative Surplus	50,400
Other MI Companies
Statutory Accounting Practices, Statutory Capital and Surplus, Additions	65,400	30,300	175,200
Statutory Accounting Practices, Statutory Capital and Surplus, Distributions	$ (14,000)	$ 0	$ 0