Other Income (Expense) - net (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income [Line Items]
Earnings on securities in nuclear decommissioning trust funds	$ 28	$ 23	$ 22
Interest income	5	3	5
Allowance for funds used during construction - equity component	11	10	10
Miscellaneous	12	18	5
Other income	56	54	42
Other Expense [Line Items]
Economic foreign currency exchange contracts	(121)	38	52
Charitable contributions	30	25	10
Spinoff of PPL Energy Supply transaction costs	19	0	0
Miscellaneous	10	14	19
Other expense	(62)	77	81
Other Income (Expense) - net	118	(23)	(39)
PPL Energy Supply LLC [Member]
Other Expense [Line Items]
Other Income (Expense) - net	30	32	19
PPL Electric Utilities Corp [Member]
Other Expense [Line Items]
Other Income (Expense) - net	7	6	9
LG And E And KU Energy LLC [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(9)	(7)	(15)
Louisville Gas And Electric Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	(3)	(2)	(3)
Kentucky Utilities Co [Member]
Other Expense [Line Items]
Other Income (Expense) - net	$ (1)	$ (3)	$ (8)