Investment Securities - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Accrued interest receivables on investment securities	$ 132		$ 132		$ 82
Impairment losses	0	$ 12	0	$ 19
Securities with a fair value, pledged as collateral	10,300		10,300		11,200
Investment Holdings [Line Items]
Unrealized losses	6,089		6,089		144
Non-rated Securities
Investment Holdings [Line Items]
Unrealized losses	$ 75		$ 75		$ 2

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of restricted 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 other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

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