v3.20.4

Debt (Narrative) (Details) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2007
Debt Instrument [Line Items] |  |  |
Outstanding debt | $ 165,451,000,000 | $ 164,557,000,000 |
Weighted-average interest rate | 4.10% | 4.40% |
Debt Instrument - principal/face amount | $ 32,241,000,000 |  |
Debt Issued in Foreign Markets |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding debt | 43,399,000,000 | $ 42,485,000,000 |
Zero Coupon |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument - principal/face amount |  |  | $ 500,000,000
Debt instrument - redemption amount | $ 592,000,000 |  |

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X
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