Other Income (Expense) - net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Other Expense [Line Items]
Other Income (Expense) - net	$ 75	$ 136	$ 61	$ 33
PPL Electric Utilities Corp [Member]
Other Expense [Line Items]
Other Income (Expense) - net	1	3	5	6
LG And E And KU Energy LLC [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(1)	(2)	(3)	(6)
Louisville Gas And Electric Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(1)	0	(3)	(3)
Kentucky Utilities Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	$ 0	$ (1)	$ 1	$ (1)