Derivative Instruments and Hedging Activities (Fair Values) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Fair Values by Balance Sheet Location [Abstract]
Asset value	$ 1,279		$ 2,097
Liability value	1,244		1,694
Derivatives Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	91	[1]	115	[1]
Liability value	52	[1]	28	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	82	[1]	73	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	82	[1],[2]	14	[1],[2]
Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			59	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	9	[1]	42	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	9	[1],[2]	1	[1],[2]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			14	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			27	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	20	[1]	27	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value			22	[1],[2]
Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1]	3	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	16	[1]	2	[1]
Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	32	[1]	1	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	28	[1]	1	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1]
Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Derivatives Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	1,188	[1]	1,982	[1]
Liability value	1,192	[1]	1,666	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	860	[1]	1,452	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	860	[1]	1,452	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	328	[1]	530	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	328	[1]	530	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	809	[1]	1,038	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1],[2]	5	[1],[2]
Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	55	[1]	23	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	750	[1]	1,010	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	383	[1]	628	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	32	[1],[2]	53	[1],[2]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	31	[1]	19	[1]
Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	320	[1]	556	[1]
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			86	[1]
Liability value
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			59	[1]
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			59	[1]
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			27	[1]
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			27	[1]
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
PPL Energy Supply LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	1,188	[1]	1,982	[1]
Liability value	1,070	[1]	1,566	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	860	[1]	1,452	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	860	[1]	1,452	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	328	[1]	530	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	328	[1]	530	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	750	[1]	1,010	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	750	[1]	1,010	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	320	[1]	556	[1]
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Commodity Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	320	[1]	556	[1]
LG And E And KU Energy LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			14	[1]
LG And E And KU Energy LLC [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Liability value	36	[1]	58	[1]
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1]	5	[1]
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1]	5	[1]
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	32	[1]	53	[1]
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	32	[1]	53	[1]
Louisville Gas And Electric Co [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value			7	[1]
Louisville Gas And Electric Co [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	[1]	5	[1]
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value
Liability value	32	[1]	53	[1]
Kentucky Utilities Co [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0		7	[1]
Kentucky Utilities Co [Member] | Derivatives Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value

[1] Represents the location on the Balance Sheets (b)        Excludes accrued interest, if applicable.

[2] Excludes accrued interest, if applicable