Risk In Force

No definition available.

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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

- Definition

Amount per life of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387

+ Details

Name:	us-gaap_ReinsuranceRetentionAmountRetainedPerLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount per life of risk ceded to reinsurer in excess of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Reinsurance - Excess-of-Loss Program (Details) - USD ($) $ in Millions	1 Months Ended					3 Months Ended	12 Months Ended
	Nov. 30, 2021	Apr. 30, 2021	Feb. 29, 2020	Apr. 30, 2019	Nov. 30, 2018	Mar. 31, 2023	Dec. 31, 2022
Mortgage
RIF						$ 66,600.0	$ 66,100.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2021-2 Ltd. \| Mortgage
RIF	$ 10,758.0					8,853.0	9,150.0
Initial and remaining coverage	484.0					449.0	472.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2021-2 Ltd. \| First layer retention \| Mortgage
First layer retention	$ 242.0					242.0	242.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2021-1 Ltd. \| Mortgage
RIF		$ 11,061.0				7,322.0	7,758.0
Initial and remaining coverage		498.0				333.0	366.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2021-1 Ltd. \| Radian Group Inc.
Proceeds from issuance of debt						45.4
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2021-1 Ltd. \| First layer retention \| Mortgage
First layer retention		$ 221.0				221.0	221.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2020-1 Ltd. \| Mortgage
RIF			$ 9,866.0			2,310.0	2,401.0
Initial and remaining coverage			488.0			347.0	368.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2020-1 Ltd. \| Radian Group Inc.
Proceeds from issuance of debt						4.4
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2020-1 Ltd. \| First layer retention \| Mortgage
First layer retention			$ 202.0			202.0	202.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2019-1 Ltd. \| Mortgage
RIF				$ 10,705.0		1,694.0	1,769.0
Initial and remaining coverage				562.0		385.0	385.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2019-1 Ltd. \| Radian Group Inc.
Proceeds from issuance of debt						7.6
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2019-1 Ltd. \| First layer retention \| Mortgage
First layer retention				$ 268.0		263.0	263.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2018-1 Ltd. \| Mortgage
RIF					$ 9,109.0	1,430.0	1,509.0
Initial and remaining coverage					434.0	276.0	276.0
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2018-1 Ltd. \| Radian Group Inc.
Proceeds from issuance of debt						3.1
Excess-of-Loss Program \| Radian Guaranty \| Eagle Re 2018-1 Ltd. \| First layer retention \| Mortgage
First layer retention					$ 205.0	$ 200.0	$ 200.0