Loans and finance receivables (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Receivables [Abstract]
Loans and finance receivables before allowances and discounts	$ 27,082	$ 26,289
Allowances for credit losses	(973)	(950)	$ (876)	$ (856)
Unamortized acquisition discounts and points	(674)	(658)
Loans and finance receivables	$ 25,435	$ 24,681

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant