BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)			12 Months Ended
	Aug. 12, 2022 $ / shares shares	Jan. 26, 2022 USD ($)	Dec. 31, 2023 USD ($) segment consecutive_trading_day $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	Oct. 31, 2021 tranche $ / shares shares
Asset Acquisition [Line Items]
Conversion ratio	0.05556
Conversion of stock, shares issued (in shares) | shares	1
Shares converted (in shares) | shares	18
Common stock, par value (in dollars per share) | $ / shares	$ 0.0001
Purchases of indefinite-lived intangible assets and transaction costs			$ 0	$ 1,300,000	$ 0
Impairment of intangible assets			$ 0	0	0
Number of reportable segments | segment			1
Reinsurance premiums payable			$ 54,400,000	119,800,000
Premiums receivable			247,100,000	111,900,000
Allowance for premiums receivable			4,000,000	2,800,000
Bad debt expense adjusted for CECL			12,500,000
Bad debt expense			14,100,000	17,400,000	20,900,000
Deferred policy acquisition cost			18,000,000	6,700,000
Amortization of deferred acquisition costs			35,100,000	22,500,000	26,400,000
Allowance for credit loss			1,800,000	200,000
Valuation allowance			$ 356,400,000	322,300,000
Amortization period			5 years
Amortization expense			$ 6,300,000	5,000,000	3,700,000
Depreciation expense			$ 1,500,000	$ 2,100,000	$ 4,600,000
Preferred stock, issued (in shares) | shares			14,100,000	14,100,000
Preferred stock, par value (in dollars per share) | $ / shares	0.0001		$ 0.0001	$ 0.0001
Term Loan | Secured debt
Asset Acquisition [Line Items]
Debt amount		$ 300,000,000
Debt instrument, term		5 years
Internet Domain Names
Asset Acquisition [Line Items]
Purchase of assets			$ 1,300,000	$ 1,300,000
Carvana
Asset Acquisition [Line Items]
Conversion price (in dollars per share) | $ / shares			$ 162.00			$ 9.00
Preferred stock, issued (in shares) | shares						14,100,000
Number of tranches | tranche						8
Investment agreement, term of agreement						5 years
Unaffiliated Texas County Mutual Insurance Company
Asset Acquisition [Line Items]
Reinsurance premiums payable			$ 60,500,000	14,200,000
Premiums receivable			$ 59,200,000	14,100,000
Stock option expense
Asset Acquisition [Line Items]
Exercisable period			10 years
Vesting period			4 years
Stock option expense | Tranche 1
Asset Acquisition [Line Items]
Vesting period			1 year
Vesting percentage			25.00%
Stock option expense | Tranche 2
Asset Acquisition [Line Items]
Vesting period			3 years
Vesting percentage			2.00%
Restricted stock unit expense | Tranche 1
Asset Acquisition [Line Items]
Vesting period			1 year
Vesting percentage			50.00%
Restricted stock unit expense | Tranche 2
Asset Acquisition [Line Items]
Vesting period			1 year
Vesting percentage			25.00%
Restricted stock unit expense | Minimum
Asset Acquisition [Line Items]
Vesting period			2 years
Restricted stock unit expense | Maximum
Asset Acquisition [Line Items]
Vesting period			4 years
Performance-based restricted stock unit expense
Asset Acquisition [Line Items]
Expected volatility rate			76.00%
Performance-based restricted stock unit expense | Monte Carlo Valuation
Asset Acquisition [Line Items]
Expected volatility rate			50.00%
Volatility, weighted-average			50.00%
Performance-based restricted stock unit expense | Minimum
Asset Acquisition [Line Items]
Vesting period			1 year
Performance-based restricted stock unit expense | Maximum
Asset Acquisition [Line Items]
Vesting period			4 years
Other Certain RSUs 1
Asset Acquisition [Line Items]
Vesting period			4 years
Other Certain RSUs 1 | Tranche 1
Asset Acquisition [Line Items]
Vesting period			1 year
Vesting percentage			25.00%
Other Certain RSUs 2 | Tranche 1
Asset Acquisition [Line Items]
Vesting period			3 years
Vesting percentage			2.00%
Other Certain RSUs 3 | Tranche 1
Asset Acquisition [Line Items]
Vesting period			1 year
Computers
Asset Acquisition [Line Items]
Useful life			3 years
Furniture
Asset Acquisition [Line Items]
Useful life			5 years
Root Property & Casualty
Asset Acquisition [Line Items]
Purchases of indefinite-lived intangible assets and transaction costs			$ 8,900,000	$ 8,900,000
Class A Shares
Asset Acquisition [Line Items]
Common stock, par value (in dollars per share) | $ / shares			$ 0.0001	$ 0.0001
Consecutive trading days | consecutive_trading_day			45
Series A Convertible Preferred Stock
Asset Acquisition [Line Items]
Conversion price (in dollars per share) | $ / shares	$ 162.00