Asset Retirement Obligations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Susquehanna Nuclear Plant ARO (Numeric) [Abstract]
Susquehanna accrued nuclear decommissioning obligation	$ 342	$ 316
Susquehanna NDT funds	864	712
Asset Retirement Obligation [Rollforward]
Balance at Beginning of Period	552	497
Accretion expense	38	36
Obligations incurred	6	9
Changes in estimated cash flow or settlement date	123	31
Effect of foreign currency exchange rates	1	1
Obligations settled	(15)	(22)
Balance at End of Period	705	552
PPL Energy Supply LLC [Member]
Susquehanna Nuclear Plant ARO (Numeric) [Abstract]
Susquehanna accrued nuclear decommissioning obligation	342	316
Susquehanna NDT funds	864	712
Asset Retirement Obligation [Rollforward]
Balance at Beginning of Period	375	359
Accretion expense	29	28
Obligations incurred	6	3
Changes in estimated cash flow or settlement date	1	(7)
Obligations settled	(7)	(8)
Balance at End of Period	404	375
LG And E And KU Energy LLC [Member]
Asset Retirement Obligation [Rollforward]
Balance at Beginning of Period	131	118
Accretion expense	7	6
Obligations incurred		6
Changes in estimated cash flow or settlement date	122	15
Obligations settled	(8)	(14)
Balance at End of Period	252	131
Louisville Gas And Electric Co [Member]
Asset Retirement Obligation [Rollforward]
Balance at Beginning of Period	62	57
Accretion expense	3	3
Changes in estimated cash flow or settlement date	17	5
Obligations settled	(8)	(3)
Balance at End of Period	74	62
Kentucky Utilities Co [Member]
Asset Retirement Obligation [Rollforward]
Balance at Beginning of Period	69	61
Accretion expense	4	3
Obligations incurred		6
Changes in estimated cash flow or settlement date	105	10
Obligations settled		(11)
Balance at End of Period	$ 178	$ 69