Restructuring and Other Costs, Before Tax (Details) - Other Operating Income (Expense) [Member] - Hartford Next Program $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 87	$ 87
Restructuring and Related Cost, Expected Cost	150	150
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	78	78
Restructuring and Related Cost, Expected Cost	78	78
Information Technology
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	0	0
Restructuring and Related Cost, Expected Cost	28	28
Professional fees and other expenses
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	9	9
Restructuring and Related Cost, Expected Cost	$ 44	$ 44