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Debt - Summary of outstanding debt (Details) | Dec. 31, 2021 USD ($) | Dec. 31, 2021 EUR (€) | Dec. 02, 2021 USD ($) | Aug. 23, 2021 USD ($) | Jan. 13, 2021 USD ($) | Dec. 31, 2020 USD ($) | May 12, 2020 USD ($)
--- | --- | --- | --- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total debt | $ 9,392,000,000 |  |  |  |  | $ 7,729,000,000 |
Less: Short-term debt and current portion of long-term debt | 1,164,000,000 |  |  |  |  | 448,000,000 |
Total long-term debt | 8,228,000,000 |  |  |  |  | 7,281,000,000 |
Other |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total debt | $ 0 |  |  |  |  | 48,000,000 |
2.80% Senior Notes due March 2021 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.80% | 2.80% |  |  | 2.80% |  |
Total debt | $ 0 |  |  |  |  | 400,000,000 |
Debt face value |  |  |  |  | $ 400,000,000 |  |
2.20% Senior Notes due November 2022 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.20% | 2.20% |  |  |  |  |
Total debt | $ 499,000,000 |  |  |  |  | 498,000,000 |
4.00% Senior Notes due November 2023 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.00% | 4.00% |  |  |  |  |
Total debt | $ 349,000,000 |  |  |  |  | 349,000,000 |
3.50% Senior Notes due June 2024 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 3.50% | 3.50% |  |  |  |  |
Total debt | $ 598,000,000 |  |  |  |  | 597,000,000 |
3.875% Senior Notes due December 2025 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 3.875% | 3.875% |  |  |  |  |
Total debt | $ 748,000,000 |  |  |  |  | 747,000,000 |
2.875% Senior Notes due May 2026 (EUR 500M) | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.875% | 2.875% |  |  |  |  |
Total debt | $ 563,000,000 |  |  |  |  | 606,000,000 |
Debt face value | € |  | € 500,000,000 |  |  |  |  |
8.205% Junior Subordinated Notes due January 2027 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 8.205% | 8.205% |  |  |  |  |
Total debt | $ 521,000,000 |  |  |  |  | 521,000,000 |
4.50% Senior Notes due December 2028 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.50% | 4.50% |  |  |  |  |
Total debt | $ 347,000,000 |  |  |  |  | 347,000,000 |
3.75% Senior Notes due May 2029 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 3.75% | 3.75% |  |  |  |  |
Total debt | $ 745,000,000 |  |  |  |  | 744,000,000 |
2.80% Senior Notes due May 2030 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.80% | 2.80% |  |  |  |  | 2.80%
Total debt | $ 993,000,000 |  |  |  |  | 992,000,000 |
Debt face value |  |  |  |  |  |  | $ 1,000,000,000
2.05% Senior Notes due August 2031 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.05% | 2.05% |  | 2.05% |  |  |
Total debt | $ 396,000,000 |  |  |  |  | 0 |
Debt face value |  |  |  | $ 400,000,000 |  |  |
2.60% Senior Notes due December 2031 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.60% | 2.60% | 2.60% |  |  |  |
Total debt | $ 496,000,000 |  |  |  |  | 0 |
Debt face value |  |  | $ 500,000,000 |  |  |  |
6.25% Senior Notes due September 2040 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 6.25% | 6.25% |  |  |  |  |
Total debt | $ 296,000,000 |  |  |  |  | 296,000,000 |
4.25% Senior Notes due December 2042 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.25% | 4.25% |  |  |  |  |
Total debt | $ 201,000,000 |  |  |  |  | 200,000,000 |
4.45% Senior Notes due May 2043 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.45% | 4.45% |  |  |  |  |
Total debt | $ 247,000,000 |  |  |  |  | 247,000,000 |
4.60% Senior Notes due June 2044 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.60% | 4.60% |  |  |  |  |
Total debt | $ 544,000,000 |  |  |  |  | 544,000,000 |
4.75% Senior Notes due May 2045 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 4.75% | 4.75% |  |  |  |  |
Total debt | $ 593,000,000 |  |  |  |  | 593,000,000 |
2.90% Senior Notes due August 2051 | Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate on debt | 2.90% | 2.90% |  | 2.90% |  |  |
Total debt | $ 591,000,000 |  |  |  |  | 0 |
Debt face value |  |  |  | $ 600,000,000 |  |  |
Commercial paper |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total debt | $ 665,000,000 |  |  |  |  | $ 0 |

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