Derivative Instruments and Hedging Activities (Risk Disclosures) (Details)	12 Months Ended								12 Months Ended
	Dec. 31, 2014 Cash Flow Hedges [Member] USD ($)	Dec. 31, 2014 Cash Flow Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 Cash Flow Hedges [Member] Cross Currency Interest Rate Swaps [Member] USD ($)	Dec. 31, 2014 Economic Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 Economic Hedges [Member] Foreign Currency Contracts [Member] USD ($)	Dec. 31, 2014 Economic Hedges [Member] Foreign Currency Contracts [Member] GBP (£)	Dec. 31, 2014 Net Investment Hedges [Member] Foreign Currency Contracts [Member] USD ($)	Dec. 31, 2014 Net Investment Hedges [Member] Foreign Currency Contracts [Member] GBP (£)	Dec. 31, 2014 Net Investment Hedges [Member] Intercompany Loans [Member]	Dec. 31, 2014 Net Investment Hedges [Member] Combined Foreign Currency Contracts And Intercompany Loans [Member]	Dec. 31, 2014 LG And E And KU Energy LLC [Member] USD ($)	Dec. 31, 2013 LG And E And KU Energy LLC [Member] USD ($)	Dec. 31, 2012 LG And E And KU Energy LLC [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] Cash Flow Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] Economic Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] USD ($)	Dec. 31, 2013 Louisville Gas And Electric Co [Member] USD ($)	Dec. 31, 2012 Louisville Gas And Electric Co [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] Cash Flow Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] Economic Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] USD ($)	Dec. 31, 2013 Kentucky Utilities Co [Member] USD ($)	Dec. 31, 2012 Kentucky Utilities Co [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] Cash Flow Hedges [Member] Interest Rate Swap Contracts [Member] USD ($)
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount		$ 1,600,000,000	$ 1,300,000,000	$ 179,000,000			$ 355,000,000	£ 217,000,000						$ 1,000,000,000	$ 179,000,000				$ 500,000,000	$ 179,000,000				$ 500,000,000
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate cash flow hedge contracts		2045												2045					2045					2045
Latest maturity date of cross-currency cash flow hedge contracts			2028
Insignificant or no hedge ineffectiveness associated with interest rate cash flow hedges	For 2014, 2013 and 2012, hedge ineffectiveness associated with interest rate derivatives was insignificant.
No or insignificant after-tax gains (losses) previously recorded in AOCI reclassified to earnings related to interest rate cash flow hedge contracts	PPL had an insignificant amount for 2014 and no such reclassifications in 2013 and 2012.
Net unrealized after-tax gains (losses) on interest rate cash flow hedge contracts expected to be reclassified into earnings during next 12 months	(10,000,000)
Cash settlement on terminated swaps											0	86,000,000	0			0	43,000,000	0			0	43,000,000	0
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts				2033											2033					2033
Foreign Currency Risk - Net Investment Hedges (Numeric) [Abstract]
Earliest settlement date of net investment hedge contracts							May 2015
Latest settlement date of net investment hedge contracts							June 2016
Net after tax gains (losses) on net investment hedges recognized in the foreign currency translation adjustment component of AOCI							14,000,000
Insignificant or no net after tax gains (losses) on net investment hedges recognized in the foreign currency translation adjustment component of AOCI									At December 31, 2014 and 2013, PPL had $14 million and an insignificant amount of accumulated net investment hedge after tax gains (losses) that were included in the foreign currency translation adjustment component of AOCI.	For 2014 and 2013, PPL recognized insignificant amounts of net investment hedge gains (losses) on the intercompany loans in the foreign currency translation adjustment component of OCI.
Foreign Currency Risk - Economic Activity (Numeric) [Abstract]
Total exposure hedged related to foreign currency contracts for anticipated earnings hedges classified as economic activity					$ 2,200,000,000	£ 1,400,000,000
Earliest termination date of foreign currency contracts for anticipated earnings hedges classified as economic activity					January 2015	January 2015
Latest termination date of foreign currency contracts for anticipated earnings hedges classified as economic activity					December 2016	December 2016