Name:	ede_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossAbstract
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- Definition

Represents net transfers in and out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ References

No definition available.

+ Details

Name:	ede_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityTransfersNet
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- Definition

Represents assets and liabilities measured at fair value using significant unobservable inputs (Level 3), which is required for the purpose of reconciliation of beginning and ending balances.

+ References

No definition available.

+ Details

Name:	ede_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityValue
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- Definition

This element represents total gains (losses) for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-SubTopic 10

-Topic 820

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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FAIR VALUE MEASUREMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Total gains or losses (realized/unrealized)
Changes in unrealized gains relating to assets still held at reporting date	$ (1,187)	$ (1,853)	$ (10,350)
Net Derivatives
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Net derivatives, beginning balance			6,208
Total gains or losses (realized/unrealized)
Included in comprehensive income			(1,738)
Transfers in and/or out of Level 3			(4,470)
Changes in unrealized gains relating to assets still held at reporting date			$ 1,738