Receivables Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Sale Of Accounts Receivable - KCPL and GMO
Accounts receivable pledged as collateral	$ 175.0	$ 175.0
Collateralized note payable	175.0	175.0
Kansas City Power and Light Company [Member]
Sale Of Accounts Receivable - KCPL and GMO
Accounts receivable pledged as collateral	110.0	110.0
Collateralized note payable	110.0	$ 110.0
Maximum amount of outstanding principal under receivables agreement	110.0
KCPL Greater Missouri Operations [Member]
Sale Of Accounts Receivable - KCPL and GMO
Maximum amount of outstanding principal under receivables agreement from mid-November to mid-June	65.0
Maximum amount of outstanding principal under receivables agreement from mid-June to mid-November	$ 80.0

Maximum amount of outstanding principal under receivables agreement

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- Definition

MaximumAmountOfOutstandingPrincipalUnderReceivablesAgreementFromMidJunToMidNov

+ References

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- Definition

MaximumAmountOfOutstandingPrincipalUnderReceivablesAgreementFromMidNovToMidJun

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- Definition

Sale Of Accounts Receivable - KCPL and GMO [Line Items] [Abstract]

+ References

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- Definition

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

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Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

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