Debt - Schedule of Assets and Liabilities Related to Asset-backed Debt Arrangements (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Prepaid expenses and other	$ 7,973	$ 7,607
Other assets	19,769	19,885
Accounts payable and accrued liabilities	23,374	23,453
Debt maturing within one year	22,633	12,973
Long-term debt	121,381	137,701
Variable Interest Entity, Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Accounts receivable, net	18,339	14,550
Prepaid expenses and other	322	1,288
Other assets	11,647	11,682
Accounts payable and accrued liabilities	37	29
Debt maturing within one year	17,312	7,483
Long-term debt	$ 8,827	$ 14,700