CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue
Net earned premium	$ 315.2	$ 172.4	$ 77.0
Ceding commission income	69.8	64.1	44.9
Net investment income	24.7	8.4	1.9
Commission and other income	20.1	11.8	4.6
Total revenue	429.8	256.7	128.4
Expense
Loss and loss adjustment expense, net	280.4	167.3	71.9
Other insurance expense	59.2	44.0	24.1
Sales and marketing	101.9	138.3	141.6
Technology development	88.8	79.6	51.8
General and administrative	129.3	122.3	72.6
Total expense	659.6	551.5	362.0
Loss before income taxes	(229.8)	(294.8)	(233.6)
Income tax expense	7.1	3.0	7.7
Net loss	(236.9)	(297.8)	(241.3)
Other comprehensive income (loss), net of tax
Unrealized gain (loss) on investments in fixed maturities	18.6	(18.4)	(5.7)
Foreign currency translation adjustment	0.0	(5.8)	0.5
Comprehensive loss	$ (218.3)	$ (322.0)	$ (246.5)
Per share data:
Net loss per share attributable to common stockholders — basic (usd per share)	$ (3.40)	$ (4.59)	$ (3.94)
Net loss per share attributable to common stockholders — diluted (usd per share)	$ (3.40)	$ (4.59)	$ (3.94)
Weighted average common shares outstanding — basic (in shares)	69,658,912	64,921,524	61,224,433
Weighted average common shares outstanding — diluted (in shares)	69,658,912	64,921,524	61,224,433