Investments - Other investments by type (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Other, net	$ 3,805	$ 4,005
Bank loans, net
Schedule of Investments [Line Items]
Other, net	1,040	1,204
Real estate
Schedule of Investments [Line Items]
Other, net	1,027	1,005
Policy loans
Schedule of Investments [Line Items]
Other, net	856	894
Agent loans, net
Schedule of Investments [Line Items]
Other, net	643	666
Derivatives and other
Schedule of Investments [Line Items]
Other, net	$ 239	$ 236