Derivatives (Schedule Of Outstanding Derivatives Entered Into To Hedge Inventory Or Fixed Price Purchase Commitments) (Details)	3 Months Ended
Mar. 31, 2016 bbl $ / bbl $ / units
Future \| Sell (Short) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	998
Weighted average contract price per gal \| $ / bbl	35.07
Future \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,354
Weighted average contract price per gal \| $ / bbl	37.02
Future \| Sell (Short) Contracts \| Diesel Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	24
Weighted average contract price per gal \| $ / bbl	1.04
Future \| Sell (Short) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	145
Weighted average contract price per gal \| $ / bbl	23.03
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	1,057
Weighted average contract price per gal \| $ / bbl	37.42
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	10
Weighted average contract price per gal \| $ / bbl	24.05
Swap \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	550
Weighted average contract price per gal \| $ / bbl	(0.38)
Swap \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	360
Weighted average contract price per gal \| $ / units	0.73
Options \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	85
Underlying, Derivative \| $ / bbl	1.76
Options \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	30
Underlying, Derivative \| $ / bbl	0.90

- 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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