Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	$ 110	$ 138	$ 235	$ 257
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	8	10	21	25
Valuation allowance adjustments	7	5	14	12
Impact of lower U.K. income tax rates relative to U.S. income tax rates	(6)	(6)	(14)	(13)
Amortization of excess deferred income taxes	(10)	(9)	(21)	(19)
Deferred tax impact of state tax reform	0	9	0	9
Interest benefit on U.K. financing entities	(3)	(4)	(6)	(9)
Kentucky recycling credit, net of federal income tax expense	(20)	0	(20)	0
Other	(2)	(1)	1	(3)
Total increase (decrease)	(26)	4	(25)	2
Total income taxes	84	142	210	259
Valuation allowance associated with Kentucky recycling credit [Member]
Increase (decrease) due to: [Abstract]
Valuation allowance adjustments	3
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	26	22	61	63
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	10	8	23	24
Amortization of excess deferred income taxes	(4)	(3)	(8)	(8)
Other	0	0	(2)	(3)
Total increase (decrease)	6	5	13	13
Total income taxes	32	27	74	76
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	23	25	56	63
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	4	3	10	11
Valuation allowance adjustments	3	0	3	0
Amortization of excess deferred income taxes	(6)	(6)	(12)	(11)
Deferred tax impact of state tax reform	0	9	0	9
Kentucky recycling credit, net of federal income tax expense	(20)	0	(20)	0
Other	(1)	0	(2)	(2)
Total increase (decrease)	(20)	6	(21)	7
Total income taxes	3	31	35	70
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	12	13	29	33
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	2	2	5	6
Valuation allowance adjustments	15	0	15	0
Amortization of excess deferred income taxes	(2)	(3)	(5)	(5)
Kentucky recycling credit, net of federal income tax expense	(15)	0	(15)	0
Other	0	0	0	(1)
Total increase (decrease)	0	(1)	0	0
Total income taxes	12	12	29	33
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	16	16	37	39
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	3	2	7	7
Valuation allowance adjustments	5	0	5	0
Amortization of excess deferred income taxes	(4)	(3)	(7)	(6)
Kentucky recycling credit, net of federal income tax expense	(5)	0	(5)	0
Other	(1)	(1)	(1)	(2)
Total increase (decrease)	(2)	(2)	(1)	(1)
Total income taxes	$ 14	$ 14	$ 36	$ 38