Investments (Supplemental Net Investment Gains (Losses)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (86)	$ 177	$ (153)
Net investment gains (losses)	(1,262)	1,529	(110)
Gains (losses) on leveraged leases and renewable energy partnerships	33	12	87
Foreign Currency Transaction Gain (Loss), Realized	182	(10)	79
Realized Investment Gains (Losses)	(880)	711	634
Debt and Equity Securities, Realized Gain (Loss)	(725)	1,229	1,056
Net investment income
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	155	518	422
Cash Flow Hedging [Member]
Net Investment Income [Line Items]
Net investment gains (losses)	19	82	207
Cash Flow Hedging [Member] \| Foreign Currency Gain (Loss) [Member] \| Reclassification out of Accumulated Other Comprehensive Income
Net Investment Income [Line Items]
Net investment gains (losses)	38	88	129
Equity Securities
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (89)	$ 77	$ (127)

Amount of realized gain (loss) on investment in debt and equity securities.

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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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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) on termination of lease before expiration of lease term.

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Amount of realized gain (loss) on investment.

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