Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Leases, Rent Expense, Net [Abstract]
Operating Leases, Rent Expense	$ 45	$ 45	$ 50
Operating leases, future minimum rental payments due
2019	26
2020	21
2021	15
2022	13
2023	8
Thereafter	33
Total	116
LG And E And KU Energy LLC [Member]
Operating Leases, Rent Expense, Net [Abstract]
Operating Leases, Rent Expense	29	26	26
Operating leases, future minimum rental payments due
2019	20
2020	15
2021	11
2022	7
2023	6
Thereafter	11
Total	70
Louisville Gas And Electric Co [Member]
Operating Leases, Rent Expense, Net [Abstract]
Operating Leases, Rent Expense	16	15	15
Operating leases, future minimum rental payments due
2019	10
2020	6
2021	4
2022	3
2023	3
Thereafter	4
Total	30
Kentucky Utilities Co [Member]
Operating Leases, Rent Expense, Net [Abstract]
Operating Leases, Rent Expense	12	$ 11	$ 11
Operating leases, future minimum rental payments due
2019	10
2020	9
2021	7
2022	4
2023	3
Thereafter	6
Total	$ 39