New Accounting Guidance Adopted (Details) $ in Millions	Dec. 31, 2021 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease Liability - Current	$ 22
Lease Liability - Noncurrent	47
Other Noncurrent Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of Use Asset	62
Louisville Gas And Electric Co [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease Liability - Current	6
Lease Liability - Noncurrent	12
Louisville Gas And Electric Co [Member] | Other Noncurrent Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of Use Asset	15
Kentucky Utilities Co [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease Liability - Current	9
Lease Liability - Noncurrent	17
Kentucky Utilities Co [Member] | Other Noncurrent Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of Use Asset	$ 24