Statutory Information - Schedule of Statutory Net Income (Loss) and Statutory Policyholders' Surplus (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Radian Guaranty
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	$ 360,049	$ 388,372
Statutory policyholders' surplus	681,204		$ 722,861
Other Mortgage Insurance Subsidiaries
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	629	(882)
Statutory policyholders' surplus	16,518		16,515
Radian Title Insurance
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	1,192	$ 1,015
Statutory policyholders' surplus	$ 44,591		$ 43,540

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477908/944-505-50-1

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- Definition

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

+ References

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