Derivatives (Outstanding Derivatives Entered Into To Hedge Inventory or Fixed Price Purchase Commitments) (Details) bbl in Thousands	12 Months Ended
Dec. 31, 2016 bbl $ / bbl $ / units
Sell (Short) [Member] \| Designated as Hedging Instrument [Member] \| Futures [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	1,295
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	49.86
Sell (Short) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	1,413
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	50.61
Sell (Short) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Diesel Futures [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	13
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	1.69
Sell (Short) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Fuel Oil Futures [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	190
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	45.91
Sell (Short) [Member] \| Not Designated As Hedging Instrument [Member] \| Swap [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	0
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	0.00
Sell (Short) [Member] \| Not Designated As Hedging Instrument [Member] \| Options [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	35
Weighted average premium received (in dollars per barrel) \| $ / bbl	1.57
Buy (Long) [Member] \| Designated as Hedging Instrument [Member] \| Futures [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	0
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	0.00
Buy (Long) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	1,349
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	51.08
Buy (Long) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Diesel Futures [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	0
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	0.00
Buy (Long) [Member] \| Not Designated As Hedging Instrument [Member] \| Futures [Member] \| Fuel Oil Futures [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	20
Weighted average contract price per bbl (in dolllars per barrel) \| $ / bbl	47.62
Buy (Long) [Member] \| Not Designated As Hedging Instrument [Member] \| Swap [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	0
Weighted average contract price per bbl (in dolllars per barrel) \| $ / units	0.00
Buy (Long) [Member] \| Not Designated As Hedging Instrument [Member] \| Options [Member] \| Crude Oil [Member]
Derivative [Line Items]
Contract volumes (1,000 bbls)	5
Weighted average premium received (in dollars per barrel) \| $ / bbl	0.23

- 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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