Condensed Financial Information (Parent Company) (Condensed Balance Sheet - Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Condensed Balance Sheet Statements, Captions [Line Items]
Amortized cost of fixed maturity securities	$ 286,816	$ 286,069
Preferred stock, par value	$ 0.01	$ 0.01
Preferred Stock, Liquidation Preference, Value	$ 3,405	$ 2,100
Common stock, par value	$ 0.01	$ 0.01
Common Stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares issued	1,171,824,242	1,168,710,101
Common stock, shares outstanding	958,613,542	1,043,588,396
Treasury stock, shares	213,210,700	125,121,705
Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Amortized cost of fixed maturity securities	$ 2,745	$ 4,520
Preferred stock, par value	$ 0.01	$ 0.01
Preferred Stock, Liquidation Preference, Value	$ 3,405	$ 2,100
Common stock, par value	$ 0.01	$ 0.01
Common Stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares issued	1,171,824,242	1,168,710,101
Common stock, shares outstanding	958,613,542	1,043,588,396
Treasury stock, shares	213,210,700	125,121,705