Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2025	Feb. 28, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Senior secured debt	$ 1,022		$ 2,284
Debt issuance costs and discounts	(432)		(369)
Total debt (average life of 11.7 years, rates averaging 5.2%)	44,576		43,031
Less amounts due within one year	3,519		4,698
Long-term debt	41,057		38,333
Senior Secured Term Loan Facility [Member]
Debt Instrument [Line Items]
Senior secured debt	0	$ 1,238	1,238
Other Senior Secured Debt [Member]
Debt Instrument [Line Items]
Other senior secured debt	1,022		1,046
Senior Unsecured Credit Facility [Member]
Debt Instrument [Line Items]
Senior unsecured debt	220		0
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured debt	$ 43,766		$ 41,116

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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