Restructuring and Other Costs, Before Tax (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		39 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	$ 1	$ 3	$ 4	$ 10
Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring			(10)	(21)
Hartford Next Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			7	18
Restructuring Reserve, Ending Balance	1	7	1	7	$ 1
Employee Severance | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring			(1)	(4)
Employee Severance | Hartford Next Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			7	18
Restructuring Reserve, Ending Balance	1	7	1	7	1
Information Technology | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring			(4)	(6)
Information Technology | Hartford Next Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			0	0
Restructuring Reserve, Ending Balance	0	0	0	0	0
Professional fees and other expenses | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring			(5)	(11)
Professional fees and other expenses | Hartford Next Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			0	0
Restructuring Reserve, Ending Balance	0	0	0	0	0
Other Operating Income (Expense) [Member] | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	1	3	4	10	123
Restructuring and Related Cost, Expected Cost	130		130		130
Other Operating Income (Expense) [Member] | Employee Severance | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	(2)	0	(5)	(7)	36
Restructuring and Related Cost, Expected Cost	36		36		36
Other Operating Income (Expense) [Member] | Information Technology | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	2	1	4	6	24
Restructuring and Related Cost, Expected Cost	24		24		24
Other Operating Income (Expense) [Member] | Professional fees and other expenses | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	1	$ 2	5	$ 11	63
Restructuring and Related Cost, Expected Cost	$ 70		$ 70		$ 70