Asset Retirement Obligations (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	$ 347
Accretion	8
Effect of foreign exchange rates	(1)
Changes in estimated timing or cost	(6)
Obligations settled	(45)
Balance at End of Period	303
LG And E And KU Energy LLC [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	296
Accretion	7
Effect of foreign exchange rates	0
Changes in estimated timing or cost	(3)
Obligations settled	(45)
Balance at End of Period	255
Louisville Gas And Electric Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	103
Accretion	2
Effect of foreign exchange rates	0
Changes in estimated timing or cost	(4)
Obligations settled	(12)
Balance at End of Period	89
Kentucky Utilities Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	193
Accretion	5
Effect of foreign exchange rates	0
Changes in estimated timing or cost	1
Obligations settled	(33)
Balance at End of Period	$ 166