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Debt - Schedule of Commercial Paper (Details) - Commercial paper - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Line of Credit Facility [Line Items] |  |
Commercial paper outstanding | $ 0.0 | $ 112.0
Weighted average commercial paper outstanding | $ 343.0 | $ 511.0
Weighted average interest rate of commercial paper outstanding | 1.47% | 0.27%

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