Debt - Assets and Liabilities Related to Asset-backed Debt Arrangements (Detail) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Prepaid expenses and other	$ 6,999	$ 7,973
Other assets	21,318	19,769
Accounts payable and accrued liabilities	19,880	23,374
Debt maturing within one year	22,067	22,633
Long-term debt	123,929	121,381
Variable Interest Entity, Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Accounts receivable, net	18,660	18,339
Prepaid expenses and other	323	322
Other assets	12,416	11,647
Accounts payable and accrued liabilities	35	37
Debt maturing within one year	16,487	17,312
Long-term debt	$ 10,114	$ 8,827