Note 1 - Description of Business and Recent Developments Level 1 (Notes)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Description and Basis of Presentation [Text Block]	Description of Business We are a diversified mortgage and real estate services business, providing both credit-related insurance coverage and other credit risk management solutions, as well as a broad array of real estate, title and mortgage services. We have two reportable business segments—Mortgage Insurance and Services. Mortgage Insurance Our Mortgage Insurance segment provides credit-related insurance coverage, principally through private mortgage insurance on residential first-lien mortgage loans, as well as other credit risk management solutions, to mortgage lending institutions and mortgage credit investors. We provide our mortgage insurance products and services mainly through our wholly-owned subsidiary, Radian Guaranty. Private mortgage insurance plays an important role in the U.S. housing finance system because it promotes affordable home ownership and helps protect mortgage lenders, investors and other beneficiaries by mitigating default-related losses on residential mortgage loans. Generally, these loans are made to home buyers who make down payments of less than 20% of the purchase price for their home or, in the case of refinancings, have less than 20% equity in their home. Private mortgage insurance also facilitates the sale of these low down payment loans in the secondary mortgage market, most of which are currently sold to the GSEs. Our total direct primary mortgage IIF and RIF were $240.6 billion and $60.9 billion, respectively, as of December 31, 2019. The GSEs and state insurance regulators impose various capital and financial requirements on our insurance subsidiaries. These include Risk-to-capital, other risk-based capital measures and surplus requirements, as well as the PMIERs financial requirements. Failure to comply with these capital and financial requirements may limit the amount of insurance that our mortgage insurance subsidiaries may write or prohibit our mortgage insurance subsidiaries from writing insurance altogether. The GSEs and state insurance regulators also possess significant discretion with respect to our mortgage insurance subsidiaries and all aspects of their business. See Note 18 for additional information on PMIERs and other regulatory information. Services Our Services segment is primarily a fee-for-service business that offers a broad array of real estate, title and mortgage services to market participants across the mortgage and real estate value chain. We offer these services primarily to mortgage lenders, financial institutions, investors and government entities. In addition, we provide title insurance and settlement services to mortgage lenders as well as directly to consumers. Our real estate services help lenders, investors and real estate agents evaluate, manage, monitor and sell properties. These real estate services include software as a service solutions and platforms, as well as managed services, such as REO asset management, real estate valuation services and real estate brokerage services. Our title services provide a comprehensive suite of insurance and non-insurance title, closing and settlement services for residential mortgage loans. Our mortgage services include a full range of services to support the single family rental business and asset class and contract underwriting to support our mortgage insurance customers. Prior to our January 2020 sale of Clayton, our mortgage services also included transaction management services, such as loan review, RMBS securitization and distressed asset reviews and servicer and loan surveillance services. See Note 7 for additional information on the sale of Clayton.