Asset Retirement Obligation, Liabilities Assumed

No definition available.

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- Definition

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.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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- Definition

Current portion of 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.

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- Definition

Amount of asset retirement obligations incurred during the period.

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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- Definition

Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Noncurrent portion of 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.

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+ Details

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

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Asset Retirement Obligations (Details) - USD ($) $ in Millions	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2018	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2018
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance, January 1	$ 405.1	$ 405.1	$ 324.0
Liabilities assumed upon merger with Great Plains Energy		412.2	0.0
Liabilities incurred during the year		7.4	13.5
Revision in timing and/or estimates	(127.0)	(138.6)	66.8
Settlements		(15.9)	(16.0)
Accretion		22.1	16.8
Ending balance		692.3	405.1
Less: current portion		(69.6)	(25.1)
Total noncurrent asset retirement obligation		622.7	380.0
Wolf Creek [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Jointly owned utility plant, proportionate ownership share				94.00%
Westar Energy Inc [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance, January 1	405.1	405.1	324.0
Liabilities assumed upon merger with Great Plains Energy		0.0	0.0
Liabilities incurred during the year		7.4	13.5
Revision in timing and/or estimates	(127.0)	(133.0)	66.8
Settlements		(10.6)	(16.0)
Accretion		14.0	16.8
Ending balance		282.9	405.1
Less: current portion		(25.1)	(25.1)
Total noncurrent asset retirement obligation		257.8	380.0
Westar Energy Inc [Member] \| Wolf Creek [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Jointly owned utility plant, proportionate ownership share				47.00%	47.00%
KCPL [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance, January 1	$ 266.3	266.3	278.0
Liabilities assumed upon merger with Great Plains Energy		0.0	0.0
Liabilities incurred during the year		0.0	0.0
Revision in timing and/or estimates		(5.7)	0.3
Settlements		(9.9)	(25.5)
Accretion		12.6	13.5
Ending balance		263.3	266.3
Less: current portion		(40.6)	(34.9)
Total noncurrent asset retirement obligation		$ 222.7	$ 231.4
KCPL [Member] \| Wolf Creek [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Jointly owned utility plant, proportionate ownership share				47.00%