Derivatives (Schedule Of Outstanding Derivatives Entered Into To Hedge Inventory Or Fixed Price Purchase Commitments) (Details)	6 Months Ended
Jun. 30, 2016 bbl $ / units $ / bbl
Future \| Sell (Short) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	965
Weighted average contract price per gal \| $ / bbl	45.06
Future \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	2,921
Weighted average contract price per gal \| $ / bbl	46.61
Future \| Sell (Short) Contracts \| Diesel Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	34
Weighted average contract price per gal \| $ / bbl	1.40
Future \| Sell (Short) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	150
Weighted average contract price per gal \| $ / bbl	34.17
Future \| Buy (Long) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Weighted average contract price per gal \| $ / bbl	0.00
Future \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	2,813
Weighted average contract price per gal \| $ / bbl	46.77
Future \| Buy (Long) Contracts \| Diesel Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	10
Weighted average contract price per gal \| $ / bbl	1.54
Future \| Buy (Long) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Weighted average contract price per gal \| $ / bbl	0.00
Swap \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	190
Weighted average contract price per gal \| $ / bbl	(1.87)
Swap \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Weighted average contract price per gal \| $ / units	0.00
Options \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	80
Underlying, Derivative \| $ / bbl	1.27
Options \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	20
Underlying, Derivative \| $ / bbl	0.26

- Definition

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract but not the derivative contract itself.

+ References

No definition available.

+ Details

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- Definition

Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract measured in volume but not the derivative contract itself.

+ References

No definition available.

+ Details

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