The total fair value of equity-based awards as of the reporting period, related to shares or units, other instruments, or cash in accordance with the terms of the arrangement.

No definition available.

+ Details

Name:	rdn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsFairValuePerShareAtPeriodEnd
Namespace Prefix:	rdn_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The market value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

No definition available.

+ Details

Name:	rdn_ShareBasedCompensationArrangementEquityInstrumentsOtherThanOptionsGrantPrice
Namespace Prefix:	rdn_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average period between the balance sheet date and expiration for equity-based awards other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan), which may be expressed in a decimal value for number of years.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-SubTopic 10

-Topic 718

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Note 16 - Share-Based and Other Compensation Plans (SARs - Cash Settled) (Details) (2008 Equity Plan [Member], Cash Settled [Member], USD $)	12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants by Compensation Committee		1,623,500	192,100
Grant Price		$ 10.42	$ 2.68
Contractual term (in years)	5
Stock Appreciation Rights (SARs) 2010 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value	$ 1.43
Stock Appreciation Rights (SARs) 2009 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value	$ 0.96