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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 2018 to 2020 under approved Clean Energy Initiative (Proposition C).

+ References

No definition available.

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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.

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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 to 2017 under approved Clean Energy Initiative (Proposition C).

+ References

No definition available.

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Represents the number of plan types that the States will choose between to meet their goals.

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No definition available.

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Represents the number of solar rebate applications processed to date.

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No definition available.

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Represents the number of states which have initiated legal challenges to the CPP, which by and large seek to invalidate the rule.

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No definition available.

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

+ References

No definition available.

+ Details

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

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No definition available.

+ Details

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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.

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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).

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Represents the amount of rebate commitments as on date.

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No definition available.

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 410
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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Commitments and Contingencies (Details 2) $ in Thousands		3 Months Ended
Commitments and Contingencies (Details 2) $ in Thousands	Jan. 09, 2016 state	Mar. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)
Environmental Laws And Regulations
Number of states initiating legal challenges to invalidate rule \| state	27
Regulatory assets of Missouri solar initiative		$ 209,934	$ 209,708
Surface Impoundments \| Asbury Power Plant \| Electric
Environmental Laws And Regulations
Asset retirement obligation		5,400
Surface Impoundments \| Asbury Power Plant \| 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)		15,000
Surface Impoundments \| Iatan \| Electric
Environmental Laws And Regulations
Asset retirement obligation		$ 4,400
Renewable Energy \| Electric
Environmental Laws And Regulations
Minimum percentage of Missouri retail sales required to generate or purchase electricity in 2014-2017		5.00%
Minimum percentage of Missouri retail sales required to generate or purchase electricity by 2018-2020		10.00%
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 solar rebate applications processed in Missouri solar initiative \| item		467
Rebate Commitments in Missouri solar initiative		$ 6,200
Regulatory assets of Missouri solar initiative		$ 6,200
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		32.00%
Number of plan types for states to choose to meet their goals \| item		2