Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 129	$ 236	$ 315	$ 467
Federal statutory tax rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 10	$ 9	$ 23	$ 22
Valuation allowance adjustments	0	3	5	9
Impact of lower U.K. income tax rates	(40)	(45)	(88)	(99)
U.S. income tax on foreign earnings - net of foreign tax credit	(7)	0	(16)	(2)
Impact of the U.K. Finance Acts	(6)	(2)	(9)	(2)
Depreciation not normalized	(2)	(3)	(5)	(4)
Interest benefit on U.K. financing entities	(4)	(4)	(8)	(9)
Stock-based compensation	(4)	(3)	(7)	(11)
Other	0	1	(5)	0
Total increase (decrease)	(53)	(44)	(110)	(96)
Total income taxes	76	192	205	371
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 44	$ 44	$ 88	$ 97
Federal statutory tax rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 9	$ 8	$ 17	$ 18
Depreciation not normalized	(2)	(2)	(4)	(3)
Stock-based compensation	(3)	(2)	(5)	(7)
Other	(1)	0	(1)	(1)
Total increase (decrease)	3	4	7	7
Total income taxes	47	48	95	104
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%	$ 49	$ 47	$ 107	$ 114
Federal statutory tax rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 5	$ 5	$ 11	$ 12
Other	(1)	(1)	(2)	(3)
Total increase (decrease)	4	4	9	9
Total income taxes	53	51	116	123
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 24	$ 22	$ 55	$ 54
Federal statutory tax rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 3	$ 2	$ 6	$ 6
Other	0	0	(1)	(1)
Total increase (decrease)	3	2	5	5
Total income taxes	27	24	60	59
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 32	$ 31	$ 67	$ 73
Federal statutory tax rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 3	$ 3	$ 7	$ 7
Other	(1)	0	(1)	0
Total increase (decrease)	2	3	6	7
Total income taxes	$ 34	$ 34	$ 73	$ 80