The number of shares available to be issued under the plan at the end of the period.

No definition available.

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Namespace Prefix:	ede_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the amount of the shelf registration statement filed with the SEC.

+ References

No definition available.

+ Details

Name:	ede_ShelfRegistrationStatementAmount
Namespace Prefix:	ede_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the information about issuance of first mortgage bonds.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount that would remain available after giving effect to issuance of first mortgage bonds.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the effective period to use proceeds under shelf registration statement to fund capital expenditures, refinancing of existing debt or general corporate needs.

+ References

No definition available.

+ Details

Name:	ede_ShelfRegistrationStatementEffectivePeriodToUseProceedsToFundCapitalExpendituresRefinancingsOfExistingDebtOrGeneralCorporateNeeds
Namespace Prefix:	ede_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the maximum amount of securities to be issued in the form of first mortgage bonds from the shelf registered with the SEC.

+ References

No definition available.

+ Details

Name:	ede_ShelfRegistrationStatementMaximumAmountOfFirstMortgageBondsToBeIssued
Namespace Prefix:	ede_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:	na
Period Type:	duration

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=us-gaap_EmployeeStockMember
Namespace Prefix:
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SHAREHOLDERS' EQUITY (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
	Dec. 13, 2013	Dec. 31, 2014	Dec. 31, 2013
SHAREHOLDERS' EQUITY
Shelf registration statement, amount	$ 200.0ede_ShelfRegistrationStatementAmount	$ 200.0ede_ShelfRegistrationStatementAmount
Maximum amount of securities to be issued in the form of first mortgage bonds		150.0
Amount that would remain available after giving effect to issuance of first mortgage bonds		90.0
Issuance of first mortgage bonds		$ 60
Effective period to use proceeds under shelf to fund capital expenditures, refinancings of existing debt or general corporate needs	3 years	3 years
Employee Stock Purchase Plan
Stock-Based Awards and Programs
Shares available for issuance		820,838	127,774
2015 Stock Incentive Plan
Stock-Based Awards and Programs
Number of shares of common stock provided for grant		500,000
401 (k) plan and ESOP
Stock-Based Awards and Programs
Shares available to be issued		196,399	256,448