Other Income (Expense) - net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Other Income [Line Items]
Earnings on securities in nuclear decommissioning trust funds	$ 7	$ 6
Interest income	1	1
Allowance for funds used during construction - equity component	4	3
Miscellaneous	5	2
Other income	17	12
Other Expense [Line Items]
Economic foreign currency exchange contracts	(88)	24
Charitable contributions	5	7
Spinoff of PPL Energy Supply transaction costs	2	0
Miscellaneous	3	4
Other expense	(78)	35
Other Income (Expense) - net	95	(23)
PPL Electric Utilities Corp [Member]
Other Expense [Line Items]
Other Income (Expense) - net	2	2
LG And E And KU Energy LLC [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(1)	(2)
Louisville Gas And Electric Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(1)	(2)
Kentucky Utilities Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	$ (1)	$ 0