Long-Term Debt (Detail) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Commercial paper	$ 1,002,000,000	$ 871,000,000
Credit Facility	0	0
Finance lease obligations	137,000,000	139,000,000
Other	56,000,000	92,000,000
Total debt	10,657,000,000	10,064,000,000
Less current portion	(358,000,000)	(684,000,000)
Long-term debt, noncurrent	10,299,000,000	9,380,000,000
Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%)
Debt Instrument [Line Items]
Senior notes	$ 348,000,000	348,000,000
Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.80%
Senior notes, face amount	$ 350,000,000
Effective interest rate	4.00%
Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%)
Debt Instrument [Line Items]
Senior notes	$ 747,000,000	747,000,000
Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.10%
Senior notes, face amount	$ 750,000,000
Effective interest rate	3.30%
Series U Notes, interest rate of 3.1%, face amount of $291, matured February 15, 2023 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Senior notes	$ 0	291,000,000
Series U Notes, interest rate of 3.1%, face amount of $291, matured February 15, 2023 (effective interest rate of 3.1%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.10%
Senior notes, face amount	$ 291,000,000
Effective interest rate	3.10%
Series V Notes, interest rate of 3.8%, face amount of $318, maturing March 15, 2025 (effective interest rate of 2.8%)
Debt Instrument [Line Items]
Senior notes	$ 324,000,000	324,000,000
Series V Notes, interest rate of 3.8%, face amount of $318, maturing March 15, 2025 (effective interest rate of 2.8%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.80%
Senior notes, face amount	$ 318,000,000
Effective interest rate	2.80%
Series W Notes, interest rate of 4.5%, face amount of $278, maturing October 1, 2034 (effective interest rate of 4.1%)
Debt Instrument [Line Items]
Senior notes	$ 289,000,000	289,000,000
Series W Notes, interest rate of 4.5%, face amount of $278, maturing October 1, 2034 (effective interest rate of 4.1%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.50%
Senior notes, face amount	$ 278,000,000
Effective interest rate	4.10%
Series X Notes, interest rate of 4.0%, face amount of $450, maturing April 15, 2028 (effective interest rate of 4.2%)
Debt Instrument [Line Items]
Senior notes	$ 446,000,000	446,000,000
Series X Notes, interest rate of 4.0%, face amount of $450, maturing April 15, 2028 (effective interest rate of 4.2%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.00%
Senior notes, face amount	$ 450,000,000
Effective interest rate	4.20%
Series Z Notes, interest rate of 4.2%, face amount of $350, maturing December 1, 2023 (effective interest rate of 4.4%)
Debt Instrument [Line Items]
Senior notes	$ 350,000,000	349,000,000
Series Z Notes, interest rate of 4.2%, face amount of $350, maturing December 1, 2023 (effective interest rate of 4.4%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.20%
Senior notes, face amount	$ 350,000,000
Effective interest rate	4.40%
Series AA Notes, interest rate of 4.7%, face amount of $300, maturing December 1, 2028 (effective interest rate of 4.8%)
Debt Instrument [Line Items]
Senior notes	$ 298,000,000	298,000,000
Series AA Notes, interest rate of 4.7%, face amount of $300, maturing December 1, 2028 (effective interest rate of 4.8%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.70%
Senior notes, face amount	$ 300,000,000
Effective interest rate	4.80%
Series CC Notes, interest rate of 3.6%, face amount of $550, maturing April 15, 2024 (effective interest rate of 3.9%)
Debt Instrument [Line Items]
Senior notes	$ 535,000,000	531,000,000
Series CC Notes, interest rate of 3.6%, face amount of $550, maturing April 15, 2024 (effective interest rate of 3.9%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.60%
Senior notes, face amount	$ 550,000,000
Effective interest rate	3.90%
Series EE Notes, interest rate of 5.8%, face amount of $600, maturing May 1, 2025 (effective interest rate of 6.0%)
Debt Instrument [Line Items]
Senior notes	$ 597,000,000	596,000,000
Series EE Notes, interest rate of 5.8%, face amount of $600, maturing May 1, 2025 (effective interest rate of 6.0%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	5.80%
Senior notes, face amount	$ 600,000,000
Effective interest rate	6.00%
Series FF Notes, interest rate of 4.6%, face amount of $1,000, maturing June 15, 2030 (effective interest rate of 4.8%)
Debt Instrument [Line Items]
Senior notes	$ 988,000,000	988,000,000
Series FF Notes, interest rate of 4.6%, face amount of $1,000, maturing June 15, 2030 (effective interest rate of 4.8%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.60%
Senior notes, face amount	$ 1,000,000,000
Effective interest rate	4.80%
Series GG Notes, interest rate of 3.5%, face amount of $1,000, maturing October 15, 2032 (effective interest rate of 3.7%)
Debt Instrument [Line Items]
Senior notes	$ 987,000,000	987,000,000
Series GG Notes, interest rate of 3.5%, face amount of $1,000, maturing October 15, 2032 (effective interest rate of 3.7%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	3.50%
Senior notes, face amount	$ 1,000,000,000
Effective interest rate	3.70%
Series HH Notes, interest rate of 2.9%, face amount of $1,100, maturing April 15, 2031 (effective interest rate of 3.0%)
Debt Instrument [Line Items]
Senior notes	$ 1,091,000,000	1,090,000,000
Series HH Notes, interest rate of 2.9%, face amount of $1,100, maturing April 15, 2031 (effective interest rate of 3.0%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	2.90%
Senior notes, face amount	$ 1,100,000,000
Effective interest rate	3.00%
Series II Notes, interest rate of 2.8%, face amount of $700, maturing October 15, 2033 (effective interest rate of 2.8%)
Debt Instrument [Line Items]
Senior notes	$ 694,000,000	694,000,000
Series II Notes, interest rate of 2.8%, face amount of $700, maturing October 15, 2033 (effective interest rate of 2.8%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	2.80%
Senior notes, face amount	$ 700,000,000
Effective interest rate	2.80%
Series JJ Notes, interest rate of 5.0%, face amount of $1,000, maturing October 15, 2027 (effective interest rate of 5.4%)
Debt Instrument [Line Items]
Senior notes	$ 985,000,000	984,000,000
Series JJ Notes, interest rate of 5.0%, face amount of $1,000, maturing October 15, 2027 (effective interest rate of 5.4%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	5.00%
Senior notes, face amount	$ 1,000,000,000
Effective interest rate	5.40%
Series KK Notes, interest rate of 4.9%, face amount of $800, maturing April 15, 2029 (effective interest rate of 5.3%)
Debt Instrument [Line Items]
Senior notes	$ 783,000,000	$ 0
Series KK Notes, interest rate of 4.9%, face amount of $800, maturing April 15, 2029 (effective interest rate of 5.3%) \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.90%
Senior notes, face amount	$ 800,000,000
Effective interest rate	5.30%

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