v2.4.0.8

Risk Management Activities (The Effect Of Derivative Instruments Reclassified To Statements Of Consolidated Income) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Cash Flow Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in OCI Derivative (Effective Portion) | $ (0.1) | $ 0.7 | $ 0 | $ 1.4
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion) | (0.4) | (0.9) | (0.7) | (2.1)
Fair Value Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | 0.2 | 0.8 | (9.5) | (8.2)
Amount of Gain Recognized in Income on Related Hedged Items | (0.2) | (0.8) | 9.5 | 8.2
Not Designated as Hedging Instrument [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | 7.7 | 17.2 | 1.3 | (5.2)
Interest Expense [Member] | Cash Flow Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion) | (0.4) | (0.7) | (0.8) | (1.3)
Cost Of Sales [Member] | Cash Flow Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion) | 0 | (0.2) | 0.1 | (0.8)
Commodity Price Risk Programs [Member] | Cash Flow Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in OCI Derivative (Effective Portion) | (0.1) | 0.3 | 0 | 0.6
Commodity Price Risk Programs [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Losses recognized in income, deferred | (7.6) | (4.7) | (1.0) | (15.1)
Commodity Price Risk Programs [Member] | Gas Distribution Revenues [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | (0.1) | (0.1) | 0 | 0.3
Commodity Price Risk Programs [Member] | Other Revenues [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | 10.8 | 7.7 | 22.8 | 6.0
Commodity Price Risk Programs [Member] | Cost Of Sales [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | (3.0) | 9.6 | (21.5) | (11.5)
Interest Rate Risk Activities [Member] | Cash Flow Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in OCI Derivative (Effective Portion) | 0 | 0.4 | 0 | 0.8
Interest Rate Risk Activities [Member] | Interest Expense [Member] | Fair Value Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Derivatives | 0.2 | 0.8 | (9.5) | (8.2)
Fixed Rate Debt Hedges [Member] | Interest Expense [Member] | Fair Value Hedging [Member] |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |
Amount of Gain Recognized in Income on Related Hedged Items | $ (0.2) | $ (0.8) | $ 9.5 | $ 8.2

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- Definition Amount of Gain (Loss) Recognized in Income on Related Hedged Items. + References No definition available. + Details
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- Definition Derivative Instruments Gain (Loss) Regulatory Deferred + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + 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 (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959 + Details
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + 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 (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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