Business Overview [Abstract]

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Debt and Equity Transactions [Abstract]

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Mortgage Insurance [Abstract]

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Other forms of credit enhancement on residential mortgage assets such as second-lien mortgages, net interest margin securities (NIMS) and primary mortgage insurance on international mortgages.

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No definition available.

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Percentage Of Non-Traditional RIF To Total RIF

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Percentage Of Pool Insurance On Domestic First-Lien Mortgages To Total Risk In Force

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Percentage Of Primary Insurance On Domestic First-Lien Mortgages To Total Risk In Force

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The amortization period related to prepaid reinsurance commissions.

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This element represents the maximum down payment percentage on a home's purchase price that is used to measure the need for private mortgage insurance.

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A commission paid on the ceded insurance risk in lieu of recapturing the risk per the initial agreement.

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Risk In Force

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No definition available.

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Represents upfront payments to the entity related to commissions on ceded insurance risk not yet earned. The amortization of this amount will be netted against the entity's deferred policy acquisition costs on the ceded policies.

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No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

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Gross amount of debt extinguished.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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No definition available.

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Amount of stock repurchase plan authorized.

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Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486086&loc=d3e24387-158525

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Note 1 - Description of Business and Recent Developments Capital and Liquidity (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jun. 18, 2015 USD ($)
Business Overview [Abstract]
Number of Reportable Segments \| segment		2
Debt and Equity Transactions [Abstract]
Stock Repurchase Program, Authorized Amount		$ 202,000			$ 202,000
Parent Company
Insurance Regulatory Capital Requirements [Abstract]
Related Party Transaction, Rate		0.00%
Debt and Equity Transactions [Abstract]
Long-term Debt, Gross		$ 1,287,863
Radian Reinsurance [Member]
Insurance Regulatory Capital Requirements [Abstract]
Proceeds from Contributions from Parent		50,000
Radian Guaranty [Member]
Insurance Regulatory Capital Requirements [Abstract]
Surplus Notes		325,000
Proceeds from Contributions from Parent		$ 100,000	$ 100,000	$ 230,400
Mortgage Insurance Segment
Mortgage Insurance [Abstract]
Private Mortgage Insurance Protects Lenders For Loans Made With This Maximum Downpayment Percentage		20.00%
Percentage Of Primary Insurance On Domestic First-Lien Mortgages To Total Risk In Force		97.40%
Risk In Force		$ 45,800,000
Percentage Of Pool Insurance On Domestic First-Lien Mortgages To Total Risk In Force		2.50%
Nontraditional Risk In Force		$ 49,400
Mortgage Insurance Segment \| Maximum [Member]
Mortgage Insurance [Abstract]
Percentage Of Non-Traditional RIF To Total RIF		1.00%
Reinsurer Concentration Risk [Member] \| Second Quota Share Reinsurance Transaction [Member] \| Radian Guaranty [Member]
Insurance Regulatory Capital Requirements [Abstract]
Profit Commission Earned on Ceded Risk		$ 8,000
Unearned Ceding Commissions		$ 8,500
Prepaid Reinsurance Commissions, Amortization Period		5 years
Senior Notes Due 2020 [Member]
Debt and Equity Transactions [Abstract]
Long-term Debt, Gross		$ 350,000
Convertible Senior Notes Due 2017 [Member]
Debt and Equity Transactions [Abstract]
Extinguishment of Debt, Amount	$ 389,100	389,100
Gain (Loss) on Repurchase of Debt Instrument	$ (91,900)	$ (91,900)