Derivatives (Schedule Of Outstanding Derivatives Entered Into Hedge Inventory Or Fixed Price Purchase Commitments) (Details)	12 Months Ended
Dec. 31, 2015 bbl $ / bbl $ / units
Selling Contracts [Member] \| Crude Oil Futures [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	37.68
Derivative, Nonmonetary Notional Amount	47
Selling Contracts [Member] \| Crude Oil Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	37.94
Derivative, Nonmonetary Notional Amount	444
Selling Contracts [Member] \| Crude oil LLSWTI swap [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	1.28
Derivative, Nonmonetary Notional Amount	290
Selling Contracts [Member] \| Diesel Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	1.30
Derivative, Nonmonetary Notional Amount	86
Selling Contracts [Member] \| Fuel Oil Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	26.97
Derivative, Nonmonetary Notional Amount	165
Selling Contracts [Member] \| Crude Oil Options [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	95
Underlying, Derivative \| $ / bbl	1.50
Buying Contracts [Member] \| Crude Oil Futures [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	0.00
Derivative, Nonmonetary Notional Amount	0
Buying Contracts [Member] \| Crude Oil Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	36.48
Derivative, Nonmonetary Notional Amount	6
Buying Contracts [Member] \| Crude oil LLSWTI swap [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / units	0.00
Derivative, Nonmonetary Notional Amount	0
Buying Contracts [Member] \| Diesel Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	1.15
Derivative, Nonmonetary Notional Amount	6
Buying Contracts [Member] \| Fuel Oil Futures [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Weighted average contract price per bbl \| $ / bbl	0.00
Derivative, Nonmonetary Notional Amount	0
Buying Contracts [Member] \| Crude Oil Options [Member] \| Not Designated As Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	35
Underlying, Derivative \| $ / bbl	0.64

- 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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