Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets [Table Text Block]

Great Plains Energy's and KCP&L's intangible assets are included in electric utility plant on the consolidated balance sheets and are detailed in the following table.

		December 31, 2013							December 31, 2012
	Gross Carrying Amount			Accumulated Amortization				Gross Carrying Amount			Accumulated Amortization
Great Plains Energy	(millions)
Computer software		$	255.4		$	(169.9	)		$	211.2		$	(152.9	)
Asset improvements		26.5			(4.9		)		26.5			(4.2		)
KCP&L
Computer software		$	231.2		$	(156.5	)		$	189.9		$	(142.9	)
Asset improvements		11.2			(1.1		)		11.2			(0.8		)

Amortization Expense Related to Intangible Assets [Table Text Block]

Great Plains Energy's and KCP&L's amortization expense related to intangible assets is detailed in the following table.

	2013		2012
	(millions)
Great Plains Energy	$	17.6	$	15.6
KCP&L	14.3		13.2

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

The following table provides the estimated amortization expense related to Great Plains Energy's and KCP&L's intangible assets for 2014 through 2018 for the intangible assets included in the consolidated balance sheets at December 31, 2013.

	2014		2015		2016		2017		2018
	(millions)
Great Plains Energy	$	17.2	$	15.1	$	13.6	$	9.5	$	6.7
KCP&L	14.0		12.1		10.7		8.4		6.3