Derivatives (Schedule Of Outstanding Derivatives Entered Into To Hedge Inventory Or Fixed Price Purchase Commitments) (Details) bbl in Thousands	6 Months Ended
Jun. 30, 2017 bbl $ / bbl
Future \| Sell (Short) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	833
Weighted average contract price per gal \| $ / bbl	46.73
Future \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	417
Weighted average contract price per gal \| $ / bbl	45.01
Future \| Sell (Short) Contracts \| RBOB Gas Futures [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	2
Weighted average contract price per gal \| $ / bbl	1.51
Future \| Sell (Short) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	235
Weighted average contract price per gal \| $ / bbl	41.96
Future \| Buy (Long) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	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 \| bbl	399
Weighted average contract price per gal \| $ / bbl	45.82
Future \| Buy (Long) Contracts \| RBOB Gas Futures [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	2
Weighted average contract price per gal \| $ / bbl	1.42
Future \| Buy (Long) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	55
Weighted average contract price per gal \| $ / bbl	42.38
Options \| Sell (Short) Contracts \| RBOB Gas Options [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	5
Underlying, Derivative \| $ / bbl	0.02
Options \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	115
Underlying, Derivative \| $ / bbl	1.16
Options \| Buy (Long) Contracts \| RBOB Gas Options [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	0
Underlying, Derivative \| $ / bbl	0.00
Options \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	60
Underlying, Derivative \| $ / bbl	0.48

- 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

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+ References

No definition available.

+ Details

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Derivatives (Schedule Of Outstanding Derivatives Entered Into To Hedge Inventory Or Fixed Price Purchase Commitments) (Details) bbl in Thousands	6 Months Ended
	Jun. 30, 2017 bbl $ / bbl
Future \| Sell (Short) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	833
Weighted average contract price per gal \| $ / bbl	46.73
Future \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	417
Weighted average contract price per gal \| $ / bbl	45.01
Future \| Sell (Short) Contracts \| RBOB Gas Futures [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	2
Weighted average contract price per gal \| $ / bbl	1.51
Future \| Sell (Short) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	235
Weighted average contract price per gal \| $ / bbl	41.96
Future \| Buy (Long) Contracts \| Crude Oil \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	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 \| bbl	399
Weighted average contract price per gal \| $ / bbl	45.82
Future \| Buy (Long) Contracts \| RBOB Gas Futures [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	2
Weighted average contract price per gal \| $ / bbl	1.42
Future \| Buy (Long) Contracts \| Fuel Oil Futures \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	55
Weighted average contract price per gal \| $ / bbl	42.38
Options \| Sell (Short) Contracts \| RBOB Gas Options [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	5
Underlying, Derivative \| $ / bbl	0.02
Options \| Sell (Short) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	115
Underlying, Derivative \| $ / bbl	1.16
Options \| Buy (Long) Contracts \| RBOB Gas Options [Member] \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	0
Underlying, Derivative \| $ / bbl	0.00
Options \| Buy (Long) Contracts \| Crude Oil \| Not Designated As Hedging Instrument
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| bbl	60
Underlying, Derivative \| $ / bbl	0.48