Restructuring and Other Costs, Before Tax (Details) - Other Operating Income (Expense) [Member] - Hartford Next Program $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 11	$ 115
Restructuring and Related Cost, Expected Cost	164	164
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	0	73
Restructuring and Related Cost, Expected Cost	73	73
Information Technology
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	2	4
Restructuring and Related Cost, Expected Cost	27	27
Professional fees and other expenses
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	9	38
Restructuring and Related Cost, Expected Cost	$ 64	$ 64