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Number of customers that account for 10 percent or more of an entity's revenues

No definition available.

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The increase (decrease) during the reporting period in goodwill and intangible assets which includes amortization, impairment, etc.

No definition available.

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This concept represents the gains and losses on investments and other financial instruments and the change in the fair value of derivative instruments for the period. This amount excludes the impact of changes in the present value of insurance claims and recoveries on insured credit derivatives and VIEs, based on the company's ongoing insurance loss monitoring, which are a component of segment expenses. This amount is used to reconcile the segment pretax operating income to net income.

No definition available.

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This concept represents the adjusted pre-tax operating income (loss) for segment reporting (non GAAP) and only includes the revenue and expense items that management considers in assessing the performance of the segment businesses.

No definition available.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses but prior to income taxes from ongoing operations.

No definition available.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
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Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=rdn_PrimaryRiskInForceMember
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Name:	us-gaap_StatementGeographicalAxis=stpr_CA
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Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_GeographicConcentrationRiskMember
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Data Type:	na
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Data Type:	na
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Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=rdn_NewInsuranceWrittenMember
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Data Type:	na
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Name:	us-gaap_MajorCustomersAxis=rdn_CustomerAMember
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Data Type:	na
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Data Type:	na
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Data Type:	na
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