The total amount of option payments for development rights required under terms of agreement.

No definition available.

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- Definition

Generating unit capacity, in megawatts.

+ References

No definition available.

+ Details

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- Definition

The number of new coal-fired generating units that may be allowed if permit issued by regulatory authority.

+ References

No definition available.

+ Details

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- Definition

The cash outflow from amounts paid for development rights under option.

+ References

No definition available.

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- Definition

Expenditures for preliminary surveys, plans and investigations for the purpose of determining the feasibility of contemplated generation and transmission projects which will be amortized over the life of the project.

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No definition available.

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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.

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No definition available.

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COMMITMENTS AND CONTINGENCIES - Purchase Option and Development Agreement (Details) $ in Thousands			12 Months Ended
	Dec. 16, 2010 facility MW	Jul. 26, 2007 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Purchase Option and Development Agreement
Preliminary surveys and investigations				$ 107,146	$ 131,693
Holcomb Station Project
Purchase Option and Development Agreement
Preliminary surveys and investigations				86,700
Holcomb Station Project \| Other Deferred Charges \| Purchase Option and Development Agreement
Purchase Option and Development Agreement
Preliminary surveys and investigations				$ 86,700
Holcomb Station Project \| Sunflower and other Sunflower parties \| Purchase Option and Development Agreement
Purchase Option and Development Agreement
Total amount of option payments		$ 55,000
Option payments made for development rights		$ 25,000	$ 5,000
Number of new coal-fired generating units if permit issued \| facility	1
Generating unit capacity (in megawatts) \| MW	895