Long-Term Debt (Detail) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Credit Facility	$ 300,000,000	$ 1,050,000,000
Finance lease obligations	143,000,000	146,000,000
Total debt	8,788,000,000	10,138,000,000
Less current portion	(558,000,000)	(805,000,000)
Long-term debt, noncurrent	8,230,000,000	9,333,000,000
Series L Notes, interest rate of 3.3%, face amount of $173, redeemed June 15, 2022 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Senior notes	0	173,000,000
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	347,000,000
Series Q Notes, interest rate of 2.3%, face amount of $399, matured January 15, 2022 (effective interest rate of 2.5%)
Debt Instrument [Line Items]
Senior notes	0	399,000,000
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	746,000,000	746,000,000
Series U Notes, interest rate of 3.1%, face amount of $291, maturing February 15, 2023 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Senior notes	291,000,000	291,000,000
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	326,000,000	327,000,000
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	290,000,000
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	445,000,000
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	349,000,000	349,000,000
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	297,000,000
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	541,000,000	566,000,000
Series DD Notes, interest rate of 2.1%, face amount of $224, maturing October 3, 2022 (effective interest rate of 1.2%)
Debt Instrument [Line Items]
Senior notes	224,000,000	226,000,000
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	596,000,000	595,000,000
Series FF Notes, interest rate of 4.6%, face amount of $1,000, maturing June 15, 2030 (effective interest rate of 4.8%)
Debt Instrument [Line Items]
Senior notes	988,000,000	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%)
Debt Instrument [Line Items]
Senior notes	986,000,000	986,000,000
Series HH Notes, interest rate of 2.9%, face amount of $1,100, maturing April 15, 2031 (effective interest rate of 3.0%)
Debt Instrument [Line Items]
Senior notes	1,090,000,000	1,090,000,000
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	693,000,000
Senior Notes \| Series L Notes, interest rate of 3.3%, face amount of $173, redeemed June 15, 2022 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Interest rate	3.30%
Senior notes, face amount	$ 173,000,000
Effective interest rate	3.40%
Senior Notes \| 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]
Interest rate	3.80%
Senior notes, face amount	$ 350,000,000
Effective interest rate	4.00%
Senior Notes \| Series Q Notes, interest rate of 2.3%, face amount of $399, matured January 15, 2022 (effective interest rate of 2.5%)
Debt Instrument [Line Items]
Interest rate	2.30%
Senior notes, face amount	$ 399,000,000
Effective interest rate	2.50%
Senior Notes \| 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]
Interest rate	3.10%
Senior notes, face amount	$ 750,000,000
Effective interest rate	3.30%
Senior Notes \| Series U Notes, interest rate of 3.1%, face amount of $291, maturing February 15, 2023 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Interest rate	3.10%
Senior notes, face amount	$ 291,000,000
Effective interest rate	3.10%
Senior Notes \| 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]
Interest rate	3.80%
Senior notes, face amount	$ 318,000,000
Effective interest rate	2.80%
Senior Notes \| 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]
Interest rate	4.50%
Senior notes, face amount	$ 278,000,000
Effective interest rate	4.10%
Senior Notes \| 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]
Interest rate	4.00%
Senior notes, face amount	$ 450,000,000
Effective interest rate	4.20%
Senior Notes \| 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]
Interest rate	4.20%
Senior notes, face amount	$ 350,000,000
Effective interest rate	4.40%
Senior Notes \| 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]
Interest rate	4.70%
Senior notes, face amount	$ 300,000,000
Effective interest rate	4.80%
Senior Notes \| 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]
Interest rate	3.60%
Senior notes, face amount	$ 550,000,000
Effective interest rate	3.90%
Senior Notes \| Series DD Notes, interest rate of 2.1%, face amount of $224, maturing October 3, 2022 (effective interest rate of 1.2%)
Debt Instrument [Line Items]
Interest rate	2.10%
Senior notes, face amount	$ 224,000,000
Effective interest rate	1.20%
Senior Notes \| 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]
Interest rate	5.80%
Senior notes, face amount	$ 600,000,000
Effective interest rate	6.00%
Senior Notes \| 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]
Interest rate	4.60%
Senior notes, face amount	$ 1,000,000,000
Effective interest rate	4.80%
Senior Notes \| 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]
Interest rate	3.50%
Senior notes, face amount	$ 1,000,000,000
Effective interest rate	3.70%
Senior Notes \| 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]
Interest rate	2.90%
Senior notes, face amount	$ 1,100,000,000
Effective interest rate	3.00%
Senior Notes \| 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]
Interest rate	2.80%
Senior notes, face amount	$ 700,000,000
Effective interest rate	2.80%
Other
Debt Instrument [Line Items]
Other	$ 133,000,000	$ 135,000,000

Amount of short-term and long-term debt and lease obligation.

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