v3.20.1

Derivative Financial Instruments (Schedule Of NYMEX Contracts And Butane Price Swap Purchase Agreements) (Details) bbl in Millions | Dec. 31, 2019 bbl
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Economic Hedges [Member] |
Derivative [Line Items] |
Derivative, Nonmonetary Notional Amount | 3.2
Economic Hedges Futures [Member] |
Derivative [Line Items] |
Derivative, Nonmonetary Notional Amount | 0.7

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