Derivative Instruments and Hedging Activities (Risk Disclosures) (Details) £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2015 GBP (£)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Net cash settlements on terminated interest rate swaps	$ 101	$ 0	$ 0
Interest Rate Swap Contracts [Member] | First Mortgage Bonds [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Principal amount						$ 1,050
Cash Flow Hedges [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Insignificant or no hedge ineffectiveness associated with interest rate cash flow hedges	For 2015, 2014 and 2013, 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	For PPL's remaining cash flow hedges, PPL had no cash flow hedges reclassified into earnings associated with discontinued cash flow hedges in 2015 and 2013 and an insignificant amount reclassified into earnings associated with discontinued cash flow hedges in 2014.
No or insignificant unrealized after-tax gains (losses) on interest rate cash flow hedge contracts expected to be reclassified into earnings during next 12 months	At December 31, 2015, the accumulated net unrecognized after-tax gains (losses) on qualifying derivatives that are expected to be reclassified into earnings during the next 12 months were insignificant.
Cash Flow Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount					$ 300
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate cash flow hedge contracts	2026
Cash Flow Hedges [Member] | Cross Currency Interest Rate Swaps [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount					1,300
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Earliest maturity date of cross-currency cash flow hedge contracts	2016
Latest maturity date of cross-currency cash flow hedge contracts	2028
Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount					179
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2033
Economic Hedges [Member] | Foreign Currency Contracts [Member]
Foreign Currency Risk - Economic Activity (Numeric) [Abstract]
Total exposure hedged related to foreign currency contracts for anticipated earnings hedges classified as economic activity				£ 1,800	2,900
Earliest termination date of foreign currency contracts for anticipated earnings hedges classified as economic activity	January 2016
Latest termination date of foreign currency contracts for anticipated earnings hedges classified as economic activity	December 2017
Net Investment Hedges [Member] | Foreign Currency Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount				£ 50	84
Foreign Currency Risk - Net Investment Hedges (Numeric) [Abstract]
Earliest settlement date of net investment hedge contracts	May 2016
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	$ 19	14
LG And E And KU Energy LLC [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Net cash settlements on terminated interest rate swaps	$ 88	0	0
LG And E And KU Energy LLC [Member] | Interest Rate Swap Contracts [Member] | First Mortgage Bonds [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Principal amount						1,050
LG And E And KU Energy LLC [Member] | Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount					179
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2033
Louisville Gas And Electric Co [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Net cash settlements on terminated interest rate swaps	$ 44	0	0
Louisville Gas And Electric Co [Member] | Interest Rate Swap Contracts [Member] | First Mortgage Bonds [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Principal amount						550
Louisville Gas And Electric Co [Member] | Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount					$ 179
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2033
Kentucky Utilities Co [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Net cash settlements on terminated interest rate swaps	$ 44	$ 0	$ 0
Kentucky Utilities Co [Member] | Interest Rate Swap Contracts [Member] | First Mortgage Bonds [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Principal amount						$ 500