Derivatives (Credit Risk on Freestanding Derivatives) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	$ 1,469	$ 1,185
Derivative, Collateral, Right to Reclaim Cash	158	238
Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	1,488	1,224
Derivatives Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	1,242	1,182
Derivatives Subject to Credit- Contingent Provisions | Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	1,300	1,222
Derivatives Not Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	227	3
Derivatives Not Subject to Credit- Contingent Provisions | Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	$ 188	$ 2