Income Taxes (Reconciliation of Income Tax Expense) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	$ 197	$ 281
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	3	24
Impact of lower U.K. income tax rates	(38)	(21)
U.S. income tax on foreign earnings - net of foreign tax credit	2	2
Foreign tax reserve adjustments		3
Federal income tax credits	(3)	(4)
Amortization of investment tax credit	(3)	(2)
Depreciation not normalized	(3)	(2)
State deferred tax rate change		(11)	[1]
Net operating loss carryforward adjustments		(6)	[2]
Other	(4)	(5)
Total increase (decrease)	(46)	(22)
Total income tax from continuing operations	151	259
PPL Energy Supply LLC [Member]
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	(26)	170
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	(6)	23
Federal income tax credits	(3)	(4)
State deferred tax rate change		(11)	[3]
Other		(1)
Total increase (decrease)	(9)	7
Total income tax from continuing operations	(35)	177
PPL Electric Utilities Corp [Member]
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	34	20
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	5	2
Federal and state tax reserve adjustments	(2)	(1)
Depreciation not normalized	(3)	(1)
Other	(1)
Total increase (decrease)	(1)
Total income tax from continuing operations	33	20
LG And E And KU Energy LLC [Member]
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	54	26
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	5	2
Amortization of investment tax credit
Net operating loss carryforward adjustments		(6)	[4]
Other	(2)	(1)
Total increase (decrease)	3	(5)
Total income tax from continuing operations	57	21
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	24	14
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	3	1
Other	(2)
Total increase (decrease)	1	1
Total income tax from continuing operations	25	15
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	36	21
Federal statutory tax rate	35.00%	35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	4	2
Other	(1)	(1)
Total increase (decrease)	3	1
Total income tax from continuing operations	$ 39	$ 22

[1] During the three months ended March 31, 2012, PPL recorded adjustments related to state deferred tax liabilities.

[2] During the three months ended March 31, 2012, PPL recorded adjustments to deferred taxes related to net operating loss carryforwards of LKE based on income tax return adjustments.

[3] During the three months ended March 31, 2012, PPL Energy Supply recorded adjustments related to state deferred tax liabilities.

[4] During the three months ended March 31, 2012, LKE recorded adjustments to deferred taxes related to net operating loss carryforwards based on income tax return adjustments.