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- Definition

First Lien Primary Mortgage Insurance Risk In Force

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This concept represents the maximum ratio of mortgage loan to total value of property for any loans acquired by a government sponsored entity (GSE).

+ References

No definition available.

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Data Type:	num:percentItemType
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- Definition

This concept represents the minimum amount of loans (expressed as a percentage) that a mortgage seller must retain participation in for loans that exceed the 80% loan to value ratio (the ratio of the loan value to the original price of the home).

+ References

No definition available.

+ Details

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Name:	rdn_MortgageInsuranceAbstract
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- Definition

This concept represents the proportionate share of the aggregate outstanding principal exposure on insured obligations.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Number Of States That Have A Statutory Or Regulatory Risk Based Capital Requirement

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No definition available.

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- Definition

Percentage Decrease In New Defaults

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No definition available.

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- Definition

Percentage Of Non-Traditional RIF To Total RIF

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No definition available.

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- Definition

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

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No definition available.

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Balance Type:	na
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- Definition

This concept represents the amount of insurance risk in force originated from 2009 through the current reporting date (which specifically excludes the legacy portfolio) as a percentage of total risk in force.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

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- Definition

The percentage of total primary mortgage insurance risk-in-force related to our legacy book of business (written prior to 2009).

+ References

No definition available.

+ Details

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- Definition

Percentage Reduction Of Net Par Outstanding

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No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

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.

+ References

No definition available.

+ Details

Name:	rdn_PrivateMortgageInsuranceProtectsLendersForLoansMadeWithLessThanThisMaximumDownPaymentPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This concept represents an entity's ratio of net risk in force (excludes risk ceded through reinsurance contracts and risk in force on defaulted loans) to the amount of statutory capital (defined as the sum of statutory policyholders' surplus plus statutory contingency reserves).

+ References

No definition available.

+ Details

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- Definition

This concept represents an entity's intended ceiling for its risk to capital ratio which is the net risk in force (excludes risk ceded through reinsurance contracts and risk in force on defaulted loans) divided by the amount of statutory capital (defined as the sum of statutory policyholders' surplus plus statutory contingency reserves).

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No definition available.

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- Definition

This concept represents the maximum ratio of net risk in force (net of risk ceded through reinsurance contracts and risk in force on defaulted loans) to statutory capital (defined as the sum of statutory policyholders' surplus plus statutory contingency reserves) allowed in those states which have statutory risk-based capital requirements.

+ References

No definition available.

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Statutory Accounting Practices, Statutory Policyholders' Surplus, Balance

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No definition available.

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- Definition

This concept represents the amount of cash (excluding any restricted cash) and other liquid investments (short-term and trading securities).

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1H

-Subparagraph (c)(2)

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-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Note 1 - Condensed Consolidated Financial Statements - Basis of Presentation and Business Overview (Details) (USD $)	3 Months Ended					70 Months Ended				0 Months Ended					3 Months Ended
	Mar. 31, 2014 segment	Mar. 31, 2014 Mortgage Insurance Segment	Mar. 31, 2014 Radian Guaranty [Member]	Dec. 31, 2013 Radian Guaranty [Member]	Mar. 31, 2014 Parent Company	Mar. 31, 2014 Radian Asset Assurance [Member]	Dec. 31, 2013 Radian Asset Assurance [Member]	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 Minimum [Member]	May 05, 2014 Clayton Holdings, LLC [Member]	Mar. 31, 2014 Less Than [Member] Mortgage Insurance Segment	Mar. 31, 2014 State Insurance Regulations [Member] Mortgage Insurance Segment state	Mar. 31, 2014 Non RBC States [Member] Maximum [Member]	Mar. 31, 2014 Non RBC States [Member] Minimum [Member]	Mar. 31, 2014 Primary Mortgage Product [Member] Mortgage Insurance Segment
Basis of Presentation and Business Overview [Line Items]
Equity Method Investment, Ownership Percentage								50.00%	20.00%
Business Overview [Abstract]
Number of Operating Segments	2
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		96.00%
First Lien Primary Mortgage Insurance Risk In Force		$ 42,100,000,000
Percentage Of Pool Insurance On Domestic First-Lien Mortgages To Total Risk In Force		3.80%
NonTraditional Risk In Force		93,000,000
Percentage Of Non-Traditional RIF To Total RIF											1.00%
Business Conditions [Abstract]
Percentage of Legacy Portfolio Risk in Force to Total Risk in Force		38.00%
Percentage of Portfolio Risk in Force Originated Since 2009 to Total Risk in Force		62.00%
Percentage Decrease In New Defaults															18.40%
Maximum Loan To Value Percentage For G.S.E. Acquired Loans		80.00%
Minimum Percentage Of The Loans In Excess Of An 80% L.T.V. Which Must Be Retained By The Mortgage Originator Or Seller		10.00%
Risk-to-capital			19.2	19.5
Number Of States That Have A Statutory Or Regulatory Risk Based Capital Requirement												16
Risk To Capital Ratio, Regulatory Maximum	25
Capital Required for Capital Adequacy													5,000,000	1,000,000
Capital and Liquidity
Percentage Reduction Of Net Par Outstanding						80.00%
Net Par Outstanding						22,700,000,000
Statutory surplus			1,305,500,000	1,317,800,000		1,186,300,000	1,198,000,000
Payments to Acquire Businesses, Gross										305,000,000
Unrestricted Cash And Liquid Investments Including Activity After The Balance Sheet Date					$ 615,000,000
Risk to Capital Ratio, Entity's Intended Maximum			20