v2.3.0.11

Risk Management Activities (Effect of Derivative Instruments on the Condensed Statements of Consolidated Income (Loss)) (Details) (USD $)
In Millions

3 Months Ended

6 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 30, 2010

Derivative Instruments Gain (Loss) Regulatory Deferred

$ 3.4

$ 4.4

$ (19.3)

$ (16.2)

Commodity Price Risk Programs [Member] | Gas Distribution Revenues [Member] | Not Designated as Hedging Instruments [Member]

Amount of Gain (Loss) Recognized in Income on Derivatives

(0.1)

^[1]

4.2

^[1]

(21.8)

^[2]

(16.8)

^[2]

Commodity Price Risk Programs [Member] | Other Income [Member] | Not Designated as Hedging Instruments [Member]

Amount of Gain (Loss) Recognized in Income on Derivatives

7.8

^[1]

(4.5)

^[1]

18.4

^[2]

72.7

^[2]

Commodity Price Risk Programs [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member]

Amount of Gain (Loss) Recognized in OCI Derivative (Effective Portion)

0.4

0.5

0.2

Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)

0.2

0.3

0.8

0.8

Commodity Price Risk Programs [Member] | Cost of Sales [Member] | Not Designated as Hedging Instruments [Member]

Amount of Gain (Loss) Recognized in Income on Derivatives

(4.5)

^[1]

(1.0)

^[1]

(7.8)

^[2]

(72.2)

^[2]

Interest Rate Risk Activities [Member] | Interest Expense [Member] | Fair Value Hedging [Member]

Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)

(0.4)

6.1

Amount of Gain (Loss) Recognized in Income on Derivatives

9.8

4.0

Interest Rate Risk Activities [Member] | Interest Expense [Member] | Cash Flow Hedging [Member]

Amount of Gain (Loss) Recognized in OCI Derivative (Effective Portion)

0.4

0.4

0.8

0.8

Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)

(0.7)

(0.7)

(1.3)

(1.3)

Fixed Rate Debt [Member] | Interest Expense [Member] | Fair Value Hedging [Member]

Amount of Gain (Loss) Recognized in Income on Related Hedged Items

(9.8)

(4.0)

0.4

(6.1)

Fair Value Hedging [Member]

Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)

(0.4)

6.1

Amount of Gain (Loss) Recognized in Income on Related Hedged Items

(9.8)

(4.0)

0.4

(6.1)

Amount of Gain (Loss) Recognized in Income on Derivatives

9.8

4.0

Cash Flow Hedging [Member]

Amount of Gain (Loss) Recognized in OCI Derivative (Effective Portion)

0.4

0.8

1.3

1.0

Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)

(0.5)

(0.4)

(0.5)

(0.5)

Not Designated as Hedging Instruments [Member]

Amount of Gain (Loss) Recognized in Income on Derivatives

$ 3.2

^[1]

$ (1.3)

^[1]

$ (11.2)

^[2]

$ (16.3)

^[2]

[1]	For the amounts of realized/unrealized gain (loss) recognized in income on derivatives disclosed in the table above, gains of $3.4 million and $4.4 million for the second quarter of 2011 and 2010, respectively, were deferred as allowed by regulatory orders. These amounts will be amortized to income over future periods of up to twelve months as specified in a regulatory order.
[2]	For the amounts of realized/unrealized gain (loss) recognized in income on derivatives disclosed in the table above, losses of $19.3 million and $16.2 million for the six months of 2011 and 2010, respectively, were deferred as allowed per regulatory orders. These amounts will be amortized to income over future periods of up to twelve months as specified in a regulatory order.

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Amount of Gain (Loss) Recognized in Income on Related Hedged Items.

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Derivative Instruments Gain (Loss) Regulatory Deferred

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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

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-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
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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 Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
-Section 50
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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