Revenue Recognition and Deferred Revenue (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2022 USD ($)
Contract with Customer, Liability, Revenue Recognized		$ 1	$ 0
Revenue from Contract with Customer, Excluding Assessed Tax	$ 10	6	25		$ 15
Contract with Customer, Receivable, after Allowance for Credit Loss	6		6			$ 7
Contract with Customer, Asset, after Allowance for Credit Loss	9		9			5
Contract with Customer, Liability	1		1			$ 1
Contract with Customer, Performance Obligation Satisfied in Previous Period	5	5
Employer Stop Loss
Revenue from Contract with Customer, Excluding Assessed Tax	2	1	7		5
Affinity Products
Revenue from Contract with Customer, Excluding Assessed Tax	5	5	10		$ 9
Commercial Auto
Revenue from Contract with Customer, Excluding Assessed Tax	2	0	5	$ 0
Product and Service, Other
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1	$ 0	$ 2	$ 0
Minimum [Member]
Employee Stop Loss Time When Base Commissions Recognized Begin and End In Months	17
Maximum [Member]
Employee Stop Loss Time When Base Commissions Recognized Begin and End In Months	21