Gallons of diesel fuel purchased annually.

No definition available.

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- Definition

Value of trading portfolio realized at a certain point in time gains (losses)

+ References

No definition available.

+ Details

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- 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

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

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- Definition

The average strike price on the group of price risk option contracts such as put options or call options.

+ References

No definition available.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)(2)

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-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (b)

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1),(2)

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- Definition

The net gain (loss) recognized in earnings in the period relating to components of the gain (loss) on price risk hedging instruments excluded from the assessment of hedge effectiveness.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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-Paragraph 4C

-Subparagraph (d)(2)

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-Paragraph 1

-Subparagraph (a)(2)

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- Definition

The estimated net amount of unrealized gains or losses on price risk cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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-Publisher FASB

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-SubTopic 30

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-Paragraph 1

-Subparagraph (c)

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- Definition

Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities.

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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-Paragraph 4F

-Subparagraph (a)

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

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-Subparagraph (SX 210.9-04.13(e))

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-Paragraph 3

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Derivatives (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Derivative Asset, Collateral, Obligation to Return Cash, Offset	$ (2.4)
Gain (Loss) on Components Excluded from Assessment of Price Risk Hedge Effectiveness			8.2
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net			5.2
Current asset (liability) for the right to reclaim cash collateral		2.2
Net unrealized and realized gains (losses) related to trading portfolio	3.2us-gaap_TradingGainsLosses	4.9us-gaap_TradingGainsLosses	8.3us-gaap_TradingGainsLosses
Gain on derivative contracts designated as hedge instruments in cash flow hedges to be reclassified from OCI into earnings during the next twelve months	4.0
Year One [Member]
Derivative [Line Items]
Value of trading portfolio realized	$ 3.7
Heating Oil [Member]
Derivative [Line Items]
Derivative, Average Price Risk Option Strike Price	3.13
Diesel Purchases [Member] \| Heating Oil [Member]
Derivative [Line Items]
Quantities under derivative contracts	56,000,000
Diesel Purchases [Member] \| Minimum [Member]
Derivative [Line Items]
Gallons of diesel fuel purchased annually	57,000,000
Diesel Purchases [Member] \| Maximum [Member]
Derivative [Line Items]
Gallons of diesel fuel purchased annually	67,000,000