Investment Securities - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Accrued interest receivables on investment securities	$ 87
Securities with a fair value, pledged as collateral	11,000	$ 8,100
Investment Holdings [Line Items]
Unrealized losses	37	$ 43
Non-rated Securities
Investment Holdings [Line Items]
Unrealized losses	$ 1

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 accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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