Name:	rdn_FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollectedWithinFiveYearsFromBalanceSheetDate
Namespace Prefix:	rdn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	rdn_FutureExpectedPremiumPaymentsNetToBeRecognizedLineItems
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Period Type:	duration

Total Future Premiums Net for Financial Guaranty Contracts with premium received greater than 20 Years from the balance sheet date.

No definition available.

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Namespace Prefix:	rdn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the first quarter of the subsequent annual period following the statement of financial position reporting date.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 163

-Paragraph 30

-Subparagraph b(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 50

-Paragraph 3

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the fourth quarter of the subsequent annual period following the statement of financial position reporting date.

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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the second quarter of the subsequent annual period following the statement of financial position reporting date.

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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the third quarter of the subsequent annual period following the statement of financial position reporting date.

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For financial guarantee insurance contracts, the aggregate amount of premium related to the premium receivable which is expected to be collected during the eleventh through fifteenth year following the statement of financial position reporting date.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 163

-Paragraph 30

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 50

-Paragraph 3

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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For financial guarantee insurance contracts, the aggregate amount of premium related to the premium receivable which is expected to be collected during the sixteenth through twentieth year following the statement of financial position reporting date.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 163

-Paragraph 30

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 50

-Paragraph 3

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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For financial guarantee insurance contracts, the aggregate amount of premium related to the premium receivable which is expected to be collected during the sixth through tenth year following the statement of financial position reporting date.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 163

-Paragraph 30

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 50

-Paragraph 3

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the fifth year following the statement of financial position reporting date.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the second year following the statement of financial position reporting date.

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Namespace Prefix:	us-gaap_
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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the fourth year following the statement of financial position reporting date.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the third year following the statement of financial position reporting date.

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Namespace Prefix:	us-gaap_
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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected during the year following the statement of financial position reporting date.

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Namespace Prefix:	us-gaap_
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For financial guarantee insurance contracts, the amount of premium related to the premium receivable which is expected to be collected over the term of the contract period.

No definition available.