STATUTORY FINANCIAL INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statutory Accounting Practices [Line Items]
Statutory Net Loss	$ (56.6)	$ (156.5)	$ (160.3)
Statutory Capital and Surplus	81.4	97.3
Root Insurance Company
Statutory Accounting Practices [Line Items]
Statutory Net Loss	(44.4)	(125.7)	(126.9)
Statutory Capital and Surplus	60.1	77.0
Authorized control level RBC	12.8	17.4
Root Property & Casualty
Statutory Accounting Practices [Line Items]
Statutory Net Loss	(12.2)	(30.8)	$ (33.4)
Statutory Capital and Surplus	21.3	20.3
Authorized control level RBC	$ 2.8	$ 4.1

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//1943274/2147479440/944-210-S99-1

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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//1943274/2147479440/944-210-S99-1

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-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479989/944-505-50-1

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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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-Topic 944
-SubTopic 505
-Section 50
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-Subparagraph (b)
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Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

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