Investments - Schedule of Investment Related Gains (Losses) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Investments, All Other Investments [Abstract]
Gross realized gains on investment activity			$ 926	$ 1,337
Gross realized losses on investment activity			(779)	(2,151)
Net realized investment gains (losses) on AFS securities			147	(814)
Net recognized investment gains (losses) on trading securities			66	(432)
Net recognized investment gains (losses) on equity securities			13	(153)
Net recognized investment gains (losses) on mortgage loans			207	(2,974)
Derivative gains (losses)			2,135	(9,173)
Provision for credit losses			(335)	(227)
Other gains (losses)			(805)	1,056
Investment related gains (losses)			$ 1,428	$ (12,717)
Derivative, gain (loss), statement of income or comprehensive income	Net gains (losses) from investment activities	Net gains (losses) from investment activities	Net gains (losses) from investment activities	Net gains (losses) from investment activities

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of gain (loss) related to nonoperating activities, classified as other.

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Amount of expense related to credit loss from transactions other than loan and lease transactions.

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Amount of realized gain (loss) on investment.

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