Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 186	$ 231
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 13	$ 13
Valuation allowance adjustments	5	6
Impact of lower U.K. income tax rates	(48)	(54)
U.S. income tax on foreign earnings - net of foreign tax credit	(9)	(2)
Impact of the U.K. Finance Acts	(3)	0
Depreciation not normalized	(3)	(1)
Interest benefit on U.K. financing entities	(4)	(5)
Stock-based compensation	(3)	(8)
Other	(5)	(1)
Total increase (decrease)	(57)	(52)
Total income taxes	129	179
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	$ 53
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 8	$ 9
Depreciation not normalized	(2)	(1)
Stock-based compensation	(2)	(5)
Other
Total increase (decrease)	4	3
Total income taxes	48	56
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%	$ 58	$ 67
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 6	$ 7
Other	(1)	(2)
Total increase (decrease)	5	5
Total income taxes	63	72
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%	$ 30	$ 32
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 3	$ 3
Total increase (decrease)	3	3
Total income taxes	33	35
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate - 35%	$ 36	$ 42
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit	$ 4	$ 4
Other	(1)	0
Total increase (decrease)	3	4
Total income taxes	$ 39	$ 46