Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	$ 146	$ 124
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	13	13
Valuation allowance adjustments	6	7
Impact of lower U.K. income tax rates relative to U.S. income tax rates	(11)	(8)
Amortization of excess deferred income taxes	(11)	(11)
Other	(3)	1
Total increase (decrease)	(6)	2
Total income tax expense (benefit)	140	126
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	33	34
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	13	13
Amortization of excess deferred income taxes	(3)	(4)
Other	(2)	(1)
Total increase (decrease)	8	8
Total income tax expense (benefit)	41	42
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	35	33
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	7	6
Amortization of excess deferred income taxes	(7)	(6)
Other	(1)	(1)
Total increase (decrease)	(1)	(1)
Total income tax expense (benefit)	34	32
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	19	17
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	4	3
Amortization of excess deferred income taxes	(3)	(3)
Other	(1)	0
Total increase (decrease)	0	0
Total income tax expense (benefit)	19	17
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	21	22
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	4	4
Amortization of excess deferred income taxes	(4)	(3)
Other	(1)	(1)
Total increase (decrease)	(1)	0
Total income tax expense (benefit)	$ 20	$ 22