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Debt - Schedule of Commercial Paper (Details) - Commercial paper - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Debt Instrument [Line Items] |  |  |
Commercial paper outstanding | $ 833 |  | $ 112
Weighted average commercial paper outstanding | $ 456 | $ 323 |
Weighted average interest rate of commercial paper outstanding | 0.96% | 0.49% |

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