Condensed Financial Information (Parent Company) (Condensed Balance Sheet - Insets) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Condensed Balance Sheet Statements, Captions [Line Items]
Amortized cost of fixed maturity securities	$ 310,811	$ 297,655
Preferred stock, par value	$ 0.01	$ 0.01
Preferred Stock, Liquidation Preference, Value	$ 4,405	$ 3,405
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares issued	1,181,614,288	1,177,680,299
Common stock, shares outstanding	892,910,600	915,338,098
Treasury stock, shares	288,703,688	262,342,201
Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Amortized cost of fixed maturity securities	$ 3,400	$ 3,062
Preferred stock, par value	$ 0.01	$ 0.01
Preferred Stock, Liquidation Preference, Value	$ 4,405	$ 3,405
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares issued	1,181,614,288	1,177,680,299
Common stock, shares outstanding	892,910,600	915,338,098
Treasury stock, shares	288,703,688	262,342,201