Note 16 - Statutory Information EnTitle Insurance (Details) - EnTitle Insurance - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 26.1
Statutory Net Income (Loss)	(0.4)
Amounts held in escrow	$ 2.4	$ 4.7

The amount as of the balance sheet date of deposits from our customers held in escrow at third party financial institutions and that is excluded from assets and liabilities in the consolidated balance sheets.

No definition available.

+ Details

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

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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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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- Details

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Namespace Prefix:
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Balance Type:
Period Type: