Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	$ 103	$ 125	$ 336	$ 359
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	15	13	39	34
Depreciation and other items not normalized	0	(2)	(4)	(5)
Valuation allowance adjustments	7	7	20	21
Impact of lower U.K. income tax rates relative to U.S. income tax rates	2	(6)	(18)	(20)
Amortization of excess deferred income taxes	(11)	(9)	(34)	(30)
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	(9)	0	(9)	1
Interest benefit on U.K. financing entities	(3)	(3)	(8)	(9)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount	1	0	5	2
Kentucky recycling credit, net of federal income tax expense	0	0	0	(20)
Other	0	(2)	(5)	3
Total increase (decrease)	106	(7)	87	(31)
Total income tax expense (benefit)	209	118	423	328
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	104	(5)	101	(8)
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	37	33	104	94
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	14	13	39	36
Depreciation and other items not normalized	0	(2)	(4)	(5)
Amortization of excess deferred income taxes	(4)	(4)	(12)	(12)
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	(4)	0	(4)	1
Other	1	0	2	0
Total increase (decrease)	7	7	21	20
Total income tax expense (benefit)	44	40	125	114
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	42	92	98
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	7	8	17	18
Valuation allowance adjustments	0	0	0	3
Amortization of excess deferred income taxes	(7)	(5)	(20)	(17)
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	(5)	1	(5)	1
Kentucky recycling credit, net of federal income tax expense	0	0	0	(20)
Other	2	(2)	0	(3)
Total increase (decrease)	(4)	1	(10)	(20)
Total income tax expense (benefit)	31	43	82	78
Amortization of Investment Tax Credit	(1)	(1)	(2)	(2)
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	18	21	50	50
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	3	4	9	9
Valuation allowance adjustments	0	0	0	15
Amortization of excess deferred income taxes	(3)	(2)	(8)	(7)
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	(2)	1	(2)	1
Kentucky recycling credit, net of federal income tax expense	0	0	0	(15)
Other	0	(2)	(2)	(2)
Total increase (decrease)	(2)	1	(3)	1
Total income tax expense (benefit)	16	22	47	51
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate	22	25	56	63
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	4	5	11	12
Valuation allowance adjustments	0	0	0	5
Amortization of excess deferred income taxes	(4)	(3)	(12)	(10)
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	(3)	0	(3)
Kentucky recycling credit, net of federal income tax expense	0	0	0	(5)
Other	0	(1)	(2)	(3)
Total increase (decrease)	(3)	1	(6)	(1)
Total income tax expense (benefit)	$ 19	$ 26	$ 50	62
Effective Income Tax Rate Reconciliation, Tax Credit, Amount				$ 0