New Accounting Guidance Pending Adoption New Accounting Guidance Pending Adoption (Details) $ in Millions |
Mar. 31, 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 |