Loans and finance receivables (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Receivables [Abstract]
Loans and finance receivables before allowances and discounts	$ 25,573	$ 24,664
Allowances for credit losses	(926)	(856)	$ (785)	$ (765)
Unamortized acquisition discounts and points	(638)	(600)
Loans and finance receivables	$ 24,009	$ 23,208

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