Derivative Instruments and Hedging Activities (Gains and Losses) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2014		Jun. 30, 2013
Cash Flow Hedges [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	$ 10		$ 58	$ (15)		$ 173
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)				2		1
Cash Flow Hedges [Member] | Other Comprehensive Income [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in OCI on derivative (effective portion)	(5)		47	(76)		129
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Other Comprehensive Income [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in OCI on derivative (effective portion)	(14)		68	(60)		77
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	(4)		(4)	(9)		(9)
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)				2
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Other Comprehensive Income [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in OCI on derivative (effective portion)	9		(21)	(16)		52
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	1		1	1		1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Other Income (Expense) Net [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)			1	(29)		70
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
Cash Flow Hedges [Member] | Commodity Contracts [Member] | Unregulated Wholesale Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	5		73	6		140
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)						1
Cash Flow Hedges [Member] | Commodity Contracts [Member] | Depreciation [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)			1	1		1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
Cash Flow Hedges [Member] | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	8		(14)	15		(30)
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
Net Investment Hedges [Member] | Foreign Currency Contracts [Member] | Other Comprehensive Income [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in OCI on derivative (effective portion)	(14)		1	(18)		17
Derivatives Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory liabilities - noncurrent			48			58
Derivatives Not Designated As Hedging Instruments [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(67)		162	(838)		153
Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory assets - noncurrent	(2)		11	(6)		15
Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(2)		(2)	(4)		(4)
Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Unregulated Wholesale Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(91)	[1]	740	(3,135)	[1]	34
Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Fuel [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	8		(3)	7		(2)
Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	78	[2]	(599)	2,442	[2]	(13)
Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Unregulated Retail Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	12		22	(52)		15
Derivatives Not Designated As Hedging Instruments [Member] | Foreign Currency Contracts [Member] | Other Income (Expense) Net [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(72)		4	(96)		123
PPL Energy Supply LLC [Member] | Cash Flow Hedges [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	13		60	22		111
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)						1
PPL Energy Supply LLC [Member] | Cash Flow Hedges [Member] | Commodity Contracts [Member] | Unregulated Wholesale Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	5		73	6		140
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)						1
PPL Energy Supply LLC [Member] | Cash Flow Hedges [Member] | Commodity Contracts [Member] | Depreciation [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)			1	1		1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
PPL Energy Supply LLC [Member] | Cash Flow Hedges [Member] | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	8		(14)	15		(30)
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	7		160	(738)		34
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Unregulated Wholesale Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(91)	[1]	740	(3,135)	[1]	34
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Fuel [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	8		(3)	7		(2)
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	78	[2]	(599)	2,442	[2]	(13)
PPL Energy Supply LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member] | Unregulated Retail Energy [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	12		22	(52)		15
LG And E And KU Energy LLC [Member] | Cash Flow Hedges [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory liabilities - noncurrent			48			58
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory assets - noncurrent	(2)		11	(6)		15
LG And E And KU Energy LLC [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(2)		(2)	(4)		(4)
Louisville Gas And Electric Co [Member] | Cash Flow Hedges [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory liabilities - noncurrent			24			29
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory assets - noncurrent	(2)		11	(6)		15
Louisville Gas And Electric Co [Member] | Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(2)		(2)	(4)		(4)
Kentucky Utilities Co [Member] | Cash Flow Hedges [Member] | Interest Rate Swaps [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in regulatory liabilities - noncurrent			$ 24			$ 29

[1] The six-month period ended June 30, 2014 includes significant realized and unrealized losses on physical and financial commodity sales contracts due to the unusually cold weather experienced in the first quarter of 2014.

[2] The six-month period ended June 30, 2014 includes significant realized and unrealized gains on physical and financial commodity purchase contracts due to the unusually cold weather experienced in the first quarter of 2014.