Investments (Equity Securities) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Unrealized Gains (Losses)	$ 712	$ 2,256
Equity securities	1,085	1,269
Common Stock
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	714	784
Equity Securities, FV-NI, Unrealized Gains (Losses)	217	295
Equity securities	931	1,079
Non-redeemable Preferred Stock
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	160	189
Equity Securities, FV-NI, Unrealized Gains (Losses)	(6)	1
Equity securities	154	190
Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	874	973
Equity Securities, FV-NI, Unrealized Gains (Losses)	211	296
Equity securities	$ 1,085	$ 1,269