Derivatives and Hedging Activities - Summary of Derivatives Bifurcated from their Related Borrowings (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Derivative [Line Items]
Fair value of assets	$ 332	$ 288
Fair value of liabilities	(271)	(392)
Net asset/(liability)	61	(104)
Notional amount	42,878,657	38,061,442
Embedded Derivatives Classified In Debt
Derivative [Line Items]
Notional amount	$ 7,383	$ 8,892

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal or face amount used to calculate payment on derivative.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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Net fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as assets, net of those classified as liabilities.

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