Schedule II: Condensed Combined Financial Information of Registrant - Statement of Operations and Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2022	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Net investment income	$ 4.0	$ 0.9	$ 0.7	$ 0.6			$ 6.2	$ 5.0	$ 5.4
Gain (Loss) on Investments	(0.6)	0.0	(0.1)	1.2			0.5	2.4	0.3
Total revenues	71.3	73.7	80.4	85.4			310.8	345.4	346.8
Operating expenses:
Sales and marketing	3.2	8.1	21.4	15.3	$ 36.7	$ 44.8	48.0	270.2	139.7
Other insurance (benefit) expense	(2.3)	1.1	(7.8)	1.0			(8.0)	5.0	(1.8)
Technology and development	9.4	14.3	17.9	13.9			55.5	65.5	52.9
General and administrative	31.0	26.4	39.5	30.5	70.0	96.4	127.4	97.6	78.5
Total operating expenses	119.0	130.8	166.7	157.4	324.1	454.9	573.9	830.6	632.1
Operating loss	(47.7)	(57.1)	(86.3)	(72.0)	(158.3)	(215.4)	(263.1)	(485.2)	(285.3)
Interest expense	(10.6)	(9.3)	(9.2)	(5.5)			(34.6)	(20.0)	(77.7)
Loss on early extinguishment of debt							0.0	(15.9)	0.0
Income tax expense	0.0	0.0	0.0	0.0			0.0	0.0	0.0
Net loss	(58.3)	(66.4)	(95.5)	(77.5)	(173.0)	(239.4)	(297.7)	(521.1)	(363.0)
Comprehensive loss	$ (57.2)	$ (68.7)	$ (96.8)	$ (81.2)	$ (178.0)	$ (246.7)	(303.9)	(526.3)	(358.0)
Parent Company
Revenues:
Net investment income							4.5	4.6	0.9
Gain (Loss) on Investments							1.2	0.0	0.0
Total revenues							5.7	4.6	0.9
Operating expenses:
Sales and marketing							11.9	10.0	0.0
Other insurance (benefit) expense							6.6	2.9	0.0
Technology and development							33.4	42.5	19.5
General and administrative							18.3	5.3	37.8
Total operating expenses							70.2	60.7	57.3
Operating loss							(64.5)	(56.1)	(56.4)
Interest expense							(34.6)	(20.0)	(77.7)
Loss on early extinguishment of debt							0.0	(15.9)	0.0
Loss before income tax expense							(99.1)	(92.0)	(134.1)
Income tax expense							0.0	0.0	0.0
Net loss before equity net loss of subsidiaries							(99.1)	(92.0)	(134.1)
Net loss of subsidiaries							(198.6)	(429.1)	(228.9)
Net loss							(297.7)	(521.1)	(363.0)
Other comprehensive (loss) income of subsidiaries							(6.2)	(5.2)	5.0
Comprehensive loss							$ (303.9)	$ (526.3)	$ (358.0)