Derivative Instruments and Hedging Activities (Intro) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014 MW	Jun. 30, 2013	Jun. 30, 2014 MW	Jun. 30, 2013	Dec. 31, 2013
Master Netting Arrangements (Numeric) [Line Items]
Obligation to return cash collateral obligation under master netting arrangement	$ 13		$ 13		$ 9
Cash collateral posted under master netting arrangements	25		25		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	22		22
No or insignificant amounts previously recorded in AOCI reclassified to earnings related to commodity price risk cash flow hedge contracts	no such reclassifications	no such reclassifications	no such reclassifications	no such reclassifications
No or immaterial hedge ineffectiveness related to commodity price risk cash flow hedge contracts	insignificant	insignificant	insignificant	insignificant
Commodity Price Risk (Non-trading) - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of economic activity derivative contracts			2019
Commodity Price Risk [Member]
Commodity Price Risk (Trading) (Numeric) [Abstract]
Trading margins gains (losses)	44		58
Unregulated Retail Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	4	20	(22)	12
Unregulated Wholesale Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(91)	590	(880)	(232)
Fuel [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	7	(4)	6	(5)
Energy Purchases [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	39	(479)	619	155
PPL Energy Supply LLC [Member]
Master Netting Arrangements (Numeric) [Line Items]
Obligation to return cash collateral obligation under master netting arrangement	13		13		9
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	22		22
No or insignificant amounts previously recorded in AOCI reclassified to earnings related to commodity price risk cash flow hedge contracts	no such reclassifications	no such reclassifications	no such reclassifications	no such reclassifications
No or immaterial hedge ineffectiveness related to commodity price risk cash flow hedge contracts	insignificant	insignificant	insignificant	insignificant
Commodity Price Risk (Non-trading) - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of economic activity derivative contracts			2019
PPL Energy Supply LLC [Member] | Commodity Price Risk [Member]
Commodity Price Risk (Trading) (Numeric) [Abstract]
Trading margins gains (losses)	44		58
PPL Energy Supply LLC [Member] | Unregulated Retail Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	4	20	(22)	12
PPL Energy Supply LLC [Member] | Unregulated Wholesale Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(91)	590	(880)	(232)
PPL Energy Supply LLC [Member] | Fuel [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	7	(4)	6	(5)
PPL Energy Supply LLC [Member] | Energy Purchases [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	39	(479)	619	155
LG And E And KU Energy LLC [Member]
Master Netting Arrangements (Numeric) [Line Items]
Cash collateral posted under master netting arrangements	21		21		22
Louisville Gas And Electric Co [Member]
Master Netting Arrangements (Numeric) [Line Items]
Cash collateral posted under master netting arrangements	$ 21		$ 21		$ 22