Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	$ 124	$ 119
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	13	15
Valuation allowance adjustments	7	7
Impact of lower U.K. income tax rates relative to U.S. income tax rates	(8)	(7)
Amortization of excess deferred income taxes	(11)	(10)
Other	1	(7)
Total increase (decrease)	2	(2)
Total income taxes	126	117
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	34	41
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	13	15
Amortization of excess deferred income taxes	(4)	(5)
Other	(1)	(2)
Total increase (decrease)	8	8
Total income taxes	42	49
LG And E And KU Energy LLC [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	33	38
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	6	8
Amortization of excess deferred income taxes	(6)	(5)
Other	(1)	(2)
Total increase (decrease)	(1)	1
Total income taxes	32	39
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	17	20
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	3	4
Amortization of excess deferred income taxes	(3)	(2)
Other	0	(1)
Total increase (decrease)	0	1
Total income taxes	17	21
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	22	23
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	4	5
Amortization of excess deferred income taxes	(3)	(3)
Other	(1)	(1)
Total increase (decrease)	0	1
Total income taxes	$ 22	$ 24