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Debt - Schedule of Commercial Paper (Details) - Commercial paper - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Line of Credit Facility [Line Items] |  |
Commercial paper outstanding | $ 112 | $ 250
Weighted average commercial paper outstanding | $ 511 | $ 580
Weighted average interest rate of commercial paper outstanding | 0.27% | 0.84%

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