Asset Retirement Obligations (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	$ 282
Accretion	4
Changes in estimated timing or cost	18
Obligations settled	(20)
Balance at End of Period	284
LG And E And KU Energy LLC [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	215
Accretion	4
Changes in estimated timing or cost	18
Obligations settled	(20)
Balance at End of Period	217
Louisville Gas And Electric Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	73
Accretion	1
Changes in estimated timing or cost	0
Obligations settled	(7)
Balance at End of Period	67
Kentucky Utilities Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	142
Accretion	3
Changes in estimated timing or cost	18
Obligations settled	(13)
Balance at End of Period	$ 150