Long-Term Debt (Detail) - USD ($) | Mar. 31, 2022 | Dec. 31, 2021 |
Debt Instrument [Line Items] | | |
Credit Facility | $ 800,000,000 | $ 1,050,000,000 |
Finance lease obligations | 144,000,000 | 146,000,000 |
Total debt | 9,469,000,000 | 10,138,000,000 |
Less current portion | (731,000,000) | (805,000,000) |
Long-term debt, noncurrent | 8,738,000,000 | 9,333,000,000 |
Series L Notes, interest rate of 3.3%, face amount of $173, maturing September 15, 2022 (effective interest rate of 3.4%) | | |
Debt Instrument [Line Items] | | |
Senior notes | 173,000,000 | 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 | 347,000,000 | 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 | 290,000,000 | 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 | 445,000,000 | 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 | 548,000,000 | 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 | 595,000,000 | 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 | 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%) | | |
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, maturing September 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 | $ 136,000,000 | $ 135,000,000 |