Represents the particulate matter primary annual standard micrograms per cubic meter of air.

No definition available.

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- Details

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- Definition

Represents the minimum percentage of retail sales which the company and investor-owned utilities in Missouri are required to generate or purchase electricity from renewable energy sources by 2021 under approved Clean Energy Initiative (Proposition C).

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the minimum percentage of retail sales which the company and investor-owned utilities in Missouri are required to generate or purchase electricity from renewable energy sources in 2014 under approved Clean Energy Initiative (Proposition C).

+ References

No definition available.

+ Details

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- Definition

Represents the fossil-fueled power plants minimum capacity, which are called by CAIR to reduce emission levels of SO2 and Nox.

+ References

No definition available.

+ Details

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Data Type:	num:powerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of comments on proposed regulation for Carbon Pollution Standards for new power plants.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents the number of groups into which the states are divided to reduce the emission levels.

+ References

No definition available.

+ Details

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- Definition

Represents the number of laws hormonized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents the number of states in which the power plants are required to reduce emission levels as per CAIR.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of states in which the power plants are required to reduce emission levels to help downwind states attain NAAQS for ozone.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents the number of strategies to achieve the best system of emission reduction identified by EPA.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents the reduction percentage of carbon emission from 2005 baseline levels by 2014, required as proposed by Clean Power Plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Percentage of Kansas retail customer peak capacity required to be sourced from renewable energy by 2016 as per renewable portfolio standard (RPS).

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of Kansas retail customer peak capacity required to be sourced from renewable energy sources by 2020 as per renewable portfolio stand (RPS).

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of Kansas retail customer peak capacity required to be sourced from renewable energy sources in 2012 as per renewable portfolio standard (RPS).

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of ownership in a coal ash impoundment at a generating facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of Missouri retail sales required to generate or purchase electricity from solar energy.

+ References

No definition available.

+ Details

Name:	ede_PercentRequirementToGenerateOrPurchaseElectricityFromSolarEnergy
Namespace Prefix:	ede_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The period of business plan which assumes normal operations, in years.

+ References

No definition available.

+ Details

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

- Definition

Represents the potential cost to be incurred for construction of new landfill and conversion of existing ash handling from wet to dry system(s), for the compliance of the proposed regulation pursuant to Federal Resource Conversation and Recovery Act (RCRA) governing the management and storage of Coal Combustion Residuals (CCR).

+ References

No definition available.

+ Details

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Namespace Prefix:	ede_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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COMMITMENTS AND CONTINGENCIES (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	0 Months Ended		1 Months Ended
	Mar. 31, 2015 state MW	Jan. 15, 2013 item	Feb. 10, 2015 item	Nov. 30, 2010
Clean Air Interstate Rule \| Electric
Environmental Laws And Regulations
Minimum capacity of power plant called to reduce emission levels of SO2 and NOx (in megawatts)	25
Number of states in which fossil-fueled power plants are required to reduce emission levels of SO2 and NOx as per CAIR	28
Cross State Air Pollution Rule
Environmental Laws And Regulations
Period of business plan	5 years
Cross State Air Pollution Rule \| Electric
Environmental Laws And Regulations
Number of states in which fossil-fueled power plants are required to reduce emission levels of SO2 and NOx as per CAIR	23
Number of states required to reduce ozone season NOx emissions to help downwind states attain NAAQS for ozone	25
Number of groups required to reduce SO2	2
NAAQS \| Electric
Environmental Laws And Regulations
Particulate matter primary annual standard (in micrograms per cubic meter of air)		12
Surface Impoundments \| Electric \| High end of range
Environmental Laws And Regulations
Potential cost for construction of new landfill and conversion of existing ash handling from wet to dry system(s)	15
Surface Impoundments \| Iatan \| Electric
Environmental Laws And Regulations
Percentage of ownership in a coal ash impoundment at a generating facility	12.00%
Surface Impoundments \| Plum point \| Electric
Environmental Laws And Regulations
Percentage of ownership in a coal ash impoundment at a generating facility	7.52%
Renewable Energy \| Electric
Environmental Laws And Regulations
Minimum percentage of Missouri retail sales required to generate or purchase electricity in 2014	5
Minimum percentage of Missouri retail sales required to generate or purchase electricity by 2021	15.00%
Percentage of Missouri retail sales required to generate or purchase solar energy	2.00%
Number of laws harmonized			2
Percentage of Kansas retail customer peak capacity required to be sourced from renewable energy in 2012				10.00%
Percentage of Kansas retail customer peak capacity required to be sourced from renewable energy by 2016				15.00%
Percentage of Kansas retail customer peak capacity required to be sourced from renewable energy by 2020				20.00%
Green House Gases
Environmental Laws And Regulations
Percentage of carbon emission reduction from 2005 baseline levels by 2030, required by the proposed Clean Power Plan	30.00%
Number of strategies to achieve the best system of emission reduction identified by EPA	4
Number of comments on proposed regulation for Carbon Pollution Standards for new power plants	2,000,000