New Accounting Guidance Pending Adoption New Accounting Guidance Pending Adoption (Details) $ in Millions	Sep. 30, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Impact of Adoption of ASU 2018-02	$ 50
LG And E And KU Energy LLC [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Impact of Adoption of ASU 2018-02	$ 18

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.

No definition available.

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