Derivative Instruments and Hedging Activities (Intro) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended		9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended				9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2014 MW	Dec. 31, 2013	Sep. 30, 2014 Commodity Price Risk [Member]	Sep. 30, 2014 Unregulated Retail Energy [Member]	Sep. 30, 2013 Unregulated Retail Energy [Member]	Sep. 30, 2014 Unregulated Retail Energy [Member]	Sep. 30, 2013 Unregulated Retail Energy [Member]	Sep. 30, 2014 Unregulated Wholesale Energy [Member]	Sep. 30, 2013 Unregulated Wholesale Energy [Member]	Sep. 30, 2014 Unregulated Wholesale Energy [Member]	Sep. 30, 2013 Unregulated Wholesale Energy [Member]	Sep. 30, 2014 Fuel [Member]	Sep. 30, 2013 Fuel [Member]	Sep. 30, 2014 Fuel [Member]	Sep. 30, 2013 Fuel [Member]	Sep. 30, 2014 Energy Purchases [Member]	Sep. 30, 2013 Energy Purchases [Member]	Sep. 30, 2014 Energy Purchases [Member]	Sep. 30, 2013 Energy Purchases [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] MW	Dec. 31, 2013 PPL Energy Supply LLC [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Commodity Price Risk [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Unregulated Retail Energy [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Unregulated Retail Energy [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Unregulated Retail Energy [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Unregulated Retail Energy [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Unregulated Wholesale Energy [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Unregulated Wholesale Energy [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Unregulated Wholesale Energy [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Unregulated Wholesale Energy [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Fuel [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Fuel [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Fuel [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Fuel [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Energy Purchases [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Energy Purchases [Member]	Sep. 30, 2014 PPL Energy Supply LLC [Member] Energy Purchases [Member]	Sep. 30, 2013 PPL Energy Supply LLC [Member] Energy Purchases [Member]	Sep. 30, 2014 LG And E And KU Energy LLC [Member]	Dec. 31, 2013 LG And E And KU Energy LLC [Member]	Sep. 30, 2014 Louisville Gas And Electric Co [Member]	Dec. 31, 2013 Louisville Gas And Electric Co [Member]
Master Netting Arrangements (Numeric) [Line Items]
Obligation to return cash collateral obligation under master netting arrangement	$ 10	$ 9																		$ 10	$ 9
Cash collateral posted under master netting arrangements	20	22																																					20	22	20	22
Commodity Price Risk (Non-trading) [Line Items]
Baseload generation fleet capacity (in MW)	7,369																			7,369
Intermediate and peaking generation fleet capacity (in MW)	3,309																			3,309
Commodity Price Risk (Non-trading) - Cash Flow Hedges (Numeric) [Abstract]
Net unrealized after-tax gains (losses) expected to be reclassified into earnings within 12 months related to commodity price risk cash flow hedge contracts	21																			21
No or insignificant amounts previously recorded in AOCI reclassified to earnings related to commodity price risk cash flow hedge contracts	There were no such reclassifications for the three and nine months ended September 30, 2014 and 2013.																			There were no such reclassifications for the three and nine months ended September 30, 2014 and 2013.
No or immaterial hedge ineffectiveness related to commodity price risk cash flow hedge contracts	For the three and nine months ended September 30, 2014 and 2013, hedge ineffectiveness associated with energy derivatives was insignificant.																			For the three and nine months ended September 30, 2014 and 2013, hedge ineffectiveness associated with energy derivatives was insignificant.
Commodity Price Risk (Non-trading) - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of economic activity derivative contracts	2019																			2019
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)				2	(2)	(20)	10	299	(49)	(581)	(281)	(9)	3	(3)	(2)	(217)	37	402	192				2	(2)	(20)	10	299	(49)	(581)	(281)	(9)	3	(3)	(2)	(217)	37	402	192
Commodity Price Risk (Trading) (Numeric) [Abstract]
Trading margins gains (losses)			$ 58																			$ 58