v3.19.3

Derivative Financial Instruments (Schedule Of NYMEX Contracts And Butane Price Swap Purchase Agreements) (Details) bbl in Millions | Sep. 30, 2019 bbl
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Economic Hedges [Member] |
Derivative [Line Items] |
Derivative, Nonmonetary Notional Amount | 4.5
Economic Hedges Futures [Member] |
Derivative [Line Items] |
Derivative, Nonmonetary Notional Amount | 1.5

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