Investments (Net Investment Income - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ (142)	$ 170
Equity Securities, FV-NI, Unrealized Gain (Loss)	(20)	107
Income (Loss) from Equity Method Investments	1,100	1,300
Net investment income
Net Investment Income [Line Items]
Debt and Equity Securities, Gain (Loss)	(523)	261
Debt and Equity Securities, Realized Gain (Loss)	69	167
Debt and Equity Securities, Unrealized Gain (Loss)	(592)	94
Unit-linked investments
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (507)	$ 197

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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