Investments (Other Invested Assets) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Document Period End Date	Sep. 30, 2020
Other invested assets	$ 2,645	$ 2,363
Equity Release Mortgages [Member]
Other invested assets	863	775
Limited Partner [Member]
Other invested assets	1,249	1,134
Derivatives
Other invested assets	174	117
Fair Value Option Contractholder Directed Unit Linked Investments [Member]
Other invested assets	258	260
Other
Other invested assets	$ 101	$ 77