Financing (Details ) $ in Millions		6 Months Ended
Jun. 11, 2015 USD ($)	Jun. 30, 2015 USD ($) item
EDE \| First mortgage bonds
Schedule of debt instruments
Maximum principal amount outstanding at any one time	$ 1,000.0
EDE \| 3.59% Series due 2030
Schedule of debt instruments
Aggregate principal amount of debt entered into a private placement	$ 60.0
Interest rate, stated percentage	3.59%
Unsecured revolving credit facility
Schedule of debt instruments
Unsecured revolving credit facility		$ 200.0
Additional borrowing capacity		$ 75.0
Number of extensions \| item		2
Extension period		1 year
Maximum percentage of total indebtedness to total capitalization under the financial covenants of the credit facility agreement		65.00%
Percentage of total indebtedness to total capitalization under the financial covenants of the credit facility agreement		53.00%
Aggregate amount of default on other indebtedness subject to cross-default under the terms of the credit facility.		$ 25.0
Outstanding borrowings		0.0
Letters of credit
Schedule of debt instruments
Unsecured revolving credit facility		20.0
Swingline loan
Schedule of debt instruments
Unsecured revolving credit facility		20.0
Commercial paper
Schedule of debt instruments
Amount of credit facility used to back up outstanding commercial paper borrowings		$ 97.0

Represents the maximum principal amount outstanding at any one time as per the terms of debt instrument covenants.

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Represents the period of extension to the maturity of debt instrument.

+ References

No definition available.

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Represents the number of extensions to the maturity of debt instrument.

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No definition available.

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- Definition

Represents the amount of additional borrowing capacity under the credit facility.

+ References

No definition available.

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- Definition

Represents the amount of the borrowing capacity under the credit facility used to back up outstanding commercial paper borrowings.

+ References

No definition available.

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- Definition

Represents the aggregate amount of default by the entity on other indebtedness subject to the cross-default provisions of the credit facility agreement.

+ References

No definition available.

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- Definition

Represents of Line Of Credit Facility Debt To Capital Ratio Covenant Compliance

+ References

No definition available.

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- Definition

Represents the maximum debt to capital ratio allowable under the financial covenant.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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