Description of Business	3 Months Ended
Description of Business	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business We are a diversified mortgage and real estate business, providing both credit-related mortgage insurance coverage and an array of other mortgage, risk, title, real estate and technology products and services. We have two reportable business segments—Mortgage and homegenius. Mortgage Our Mortgage segment provides credit-related insurance coverage, principally through private mortgage insurance on residential first-lien mortgage loans, as well as other credit risk management, contract underwriting and fulfillment 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 and investors, as well as other beneficiaries, by mitigating default-related losses on residential mortgage loans. Generally, these loans are made to homebuyers 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 $249.0 billion and $62.0 billion, respectively, as of March 31, 2022, compared to $246.0 billion and $60.9 billion, respectively, as of December 31, 2021. In addition to providing private mortgage insurance, we have participated in credit risk transfer programs developed by the GSEs as part of their initiative to distribute mortgage credit risk and increase the role of private capital in the mortgage market. Our additional RIF under credit risk transfer transactions, resulting from our participation in these programs with the GSEs, totaled $405.9 million as of March 31, 2022 compared to $417.7 million as of December 31, 2021. The GSEs and state insurance regulators impose various capital and financial requirements on our mortgage 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 write, or may prohibit them from writing insurance altogether. The GSEs and state insurance regulators possess significant discretion with respect to our mortgage insurance subsidiaries and all aspects of their business. See Note 16 for additional information on PMIERs and other regulatory information. homegenius Our homegenius segment is primarily a fee-for-service business that offers an array of products and services to market participants across the real estate value chain. Our homegenius products and services include title, real estate and technology products and services offered primarily to consumers, mortgage lenders, mortgage and real estate investors, GSEs, real estate brokers and agents. These products and services help lenders, investors, consumers and real estate agents evaluate, manage, monitor, acquire and sell properties, and include SaaS solutions and platforms, as well as managed services, such as real estate owned asset management, single family rental services and real estate valuation services. In addition, we provide title insurance and non-insurance title, closing and settlement services to mortgage lenders, GSEs and mortgage investors, as well as directly to consumers for residential mortgage loans. See Note 4 for additional information about our reportable segments and All Other business activities. Risks and Uncertainties The Company is subject to risks and uncertainties that could affect amounts reported in its financial statements in future periods and that could cause actual results to be materially different from its estimates, including as a result of macroeconomic stresses such as those that may result from reoccurring COVID-19 outbreaks and the ongoing Russia-Ukraine conflict. In assessing the Company’s current financial condition and developing forecasts of future operations, management has made significant judgments and estimates with respect to the potential financial and liquidity effects of the Company’s risks and uncertainties.