Restructuring and Related Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs	$ 1	$ 104	$ 0
Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	(37)	(50)
Hartford Next Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	(11)	(19)
Hartford Next Program | Information Technology
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	(9)	(2)
Hartford Next Program | Professional fees and other expenses
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	(17)	(29)
Hartford Next Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	18	54	0
Hartford Next Program | Other liabilities | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	18	54	0
Restructuring Reserve, Period Increase (Decrease)	25
Hartford Next Program | Other liabilities | Information Technology
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0	0	0
Hartford Next Program | Other liabilities | Professional fees and other expenses
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0	0	$ 0
Other Operating Income (Expense) [Member] | Hartford Next Program
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	130
Restructuring and other costs	1	104
Other Operating Income (Expense) [Member] | Hartford Next Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	48
Restructuring and other costs	25	73
Other Operating Income (Expense) [Member] | Hartford Next Program | Information Technology
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	21
Restructuring and other costs	9	2
Other Operating Income (Expense) [Member] | Hartford Next Program | Professional fees and other expenses
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	61
Restructuring and other costs	$ 17	$ 29