Derivatives (Schedule Of Outstanding Derivatives Entered Into To Hedge Inventory Or Fixed Price Purchase Commitments) (Details)	9 Months Ended
Sep. 30, 2016 bbl $ / units $ / bbl
Future \| Sell (Short) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,058
Weighted average contract price per gal \| $ / bbl	45.24
Future \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,440
Weighted average contract price per gal \| $ / bbl	44.77
Future \| Sell (Short) Contracts \| Diesel Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	18
Weighted average contract price per gal \| $ / bbl	1.41
Future \| Sell (Short) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	105
Weighted average contract price per gal \| $ / bbl	35.73
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	1,388
Weighted average contract price per gal \| $ / bbl	44.96
Future \| Buy (Long) Contracts \| Diesel Futures \| Not 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 \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	45
Weighted average contract price per gal \| $ / bbl	37.02
Swap \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Weighted average contract price per gal \| $ / bbl	0.00
Swap \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	60
Weighted average contract price per gal \| $ / units	(1.88)
Options \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	55
Underlying, Derivative \| $ / bbl	1.55
Options \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	10
Underlying, Derivative \| $ / bbl	0.36

- 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

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+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

+ Details

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