Derivative Instruments and Hedging Activities (Gains and Losses) (Details) (USD $) In Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
Credit Risk-Related Contingent Features
Aggregate fair value of derivative instruments with credit contingent provisions	88				88
Collateral posted on the derivative instruments	61				61
Additional collateral requirements in the event of a credit downgrade below investment grade	184	[1]			184	[1]
Fair Value Hedges | Interest Rate Swaps [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Hedged items in fair value hedging relationships	Fixed rate debt		Fixed rate debt		Fixed rate debt		Fixed rate debt
Fair Value Hedges | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	1		16		2		34
Gain (loss) recognized in income on related item	8		(6)		18		(13)
Cash Flow Hedges
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in OCI (effective portion) on derivative	(51)		(265)		18		374
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	144		8		264		105
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	(26)		(51)		(34)		(185)
Cash Flow Hedges | Interest Rate Swaps [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in OCI (effective portion) on derivative	(9)		(93)		1		(101)
Cash Flow Hedges | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	(3)		0		(6)		(1)
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	(12)		0		(13)		(3)
Cash Flow Hedges | Cross-Currency Swaps [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in OCI (effective portion) on derivative	(8)		24		(33)		46
Cash Flow Hedges | Cross-Currency Swaps [Member] | Interest Expense [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	0		1		3		1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0		0		0		0
Cash Flow Hedges | Cross-Currency Swaps [Member] | Other Income (Expense) Net [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	30		16		17		38
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0		0		0		0
Cash Flow Hedges | Commodity Contracts [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in OCI (effective portion) on derivative	(34)		(196)		50		429
Cash Flow Hedges | Commodity Contracts [Member] | Wholesale Energy Marketing [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	164		198		367		376
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	(14)		(52)		(22)		(165)
Cash Flow Hedges | Commodity Contracts [Member] | Fuel [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)			0				1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)			0				0
Cash Flow Hedges | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)	(47)		(207)		(117)		(311)
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0		1		1		(17)
Cash Flow Hedges | Commodity Contracts [Member] | Depreciation [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) reclassified from AOCI into income on derivative (effective portion)			0				1
Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)			0				0
Derivatives Not Designated as Hedging Instruments
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	79		(201)		90		(159)
Derivatives Not Designated as Hedging Instruments | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	(2)				(4)
Derivatives Not Designated as Hedging Instruments | Interest Rate Swaps [Member] | Regulatory Assets [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gains (losses) recognized as regulatory asset on derivative	(3)				(1)
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Wholesale Energy Marketing [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	(71)		(435)		(26)		323
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Fuel [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	(8)		(13)		15		(12)
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Energy Purchases [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	91		244		36		(495)
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Unregulated Retail Electric and Gas [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	4		1		5		12
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Net Energy Trading Margins [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	4	[2]	2	[2]	11	[2]	11	[2]
Derivatives Not Designated as Hedging Instruments | Commodity Contracts [Member] | Utility Revenue [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	(3)				(2)
Derivatives Not Designated as Hedging Instruments | Foreign Currency Exchange Contracts [Member] | Other Income (Expense) Net [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in income on derivative	64		0		55		2
Net Investment Hedges | Foreign Currency Exchange Contracts [Member]
Amounts Included In Income Statement Or Oci [Abstract]
Gain (loss) recognized in OCI (effective portion) on derivative	0		1		(1)		5

[1] Includes the effect of net receivables and payables already recorded on the Balance Sheet.

[2] Differs from the Statement of Income due to intra-month transactions that PPL defines as spot activity, which is not accounted for as a derivative.