Investments (Net Investment Income - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ (508)	$ (142)
Equity Securities, FV-NI, Unrealized Gain (Loss)	41	(20)
Income (Loss) from Equity Method Investments	(93)	1,088
Net investment income
Net Investment Income [Line Items]
Debt and Equity Securities, Gain (Loss)	360	(523)
Debt and Equity Securities, Realized Gain (Loss)	38	69
Debt and Equity Securities, Unrealized Gain (Loss)	322	(592)
Unit-linked investments
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 313	$ (507)

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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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