Available-for-Sale Securities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Dec. 31, 2012
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	$ 508				$ 508				$ 494
Gross unrealized gains	318				318				239
Gross unrealized losses	3				3				2
Fair value	823				823				731
Available-for-Sale Securities Scheduled Maturity Dates of Debt Securities (Details) [Abstract]
Amortized cost - maturity less than 1 year	6				6
Amortized cost - maturity between 1 and 5 years	92				92
Amortized cost - maturity between 6 and 10 years	56				56
Amortized cost - maturity in excess of 10 years	77				77
Amortized cost total	231				231
Fair value - maturity less than 1 year	6				6
Fair value - maturity between 1 and 5 years	96				96
Fair value - maturity between 6 and 10 years	58				58
Fair value - maturity in excess of 10 years	79				79
Fair value total	239				239
Available-for-Sale Securities Proceeds From and Realized Gains and Losses (Details) [Abstract]
Proceeds from sales of NDT securities	33	[1]	23	[1]	92		102
Other proceeds from sales							5
Gross realized gains	3	[2]	2	[2]	10	[2]	15	[2]
Gross realized losses	2	[2]	2	[2]	6	[2]	8	[2]
Nuclear Decommissioning Trust Funds [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	488				488				474
Gross unrealized gains	318				318				239
Gross unrealized losses	2				2				1
Fair value	804				804				712
Nuclear Decommissioning Trust Funds [Member] | Cash And Cash Equivalents [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	14				14				11
Gross unrealized gains
Gross unrealized losses
Fair value	14				14				11
Nuclear Decommissioning Trust Funds [Member] | United States Large Cap Equity Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	230				230				222
Gross unrealized gains	264				264				190
Gross unrealized losses
Fair value	494				494				412
Nuclear Decommissioning Trust Funds [Member] | United States Mid Small Cap Equity Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	31				31				30
Gross unrealized gains	43				43				30
Gross unrealized losses
Fair value	74				74				60
Nuclear Decommissioning Trust Funds [Member] | United States Treasury Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	90				90				86
Gross unrealized gains	6				6				9
Gross unrealized losses
Fair value	96				96				95
Nuclear Decommissioning Trust Funds [Member] | United States Government Sponsored Agency Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	5				5				8
Gross unrealized gains	1				1				1
Gross unrealized losses
Fair value	6				6				9
Nuclear Decommissioning Trust Funds [Member] | Municipality Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	74				74				78
Gross unrealized gains	2				2				5
Gross unrealized losses	1				1				1
Fair value	75				75				82
Nuclear Decommissioning Trust Funds [Member] | Investment Grade Corporate Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	39				39				36
Gross unrealized gains	2				2				4
Gross unrealized losses	1				1
Fair value	40				40				40
Nuclear Decommissioning Trust Funds [Member] | Other Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	3				3				3
Gross unrealized gains
Gross unrealized losses
Fair value	3				3				3
Nuclear Decommissioning Trust Funds [Member] | Receivables Payables Net [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	2				2
Gross unrealized gains
Gross unrealized losses
Fair value	2				2
Auction Rate Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	20				20				20
Gross unrealized gains
Gross unrealized losses	1				1				1
Fair value	19				19				19
PPL Energy Supply LLC [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	505				505				491
Gross unrealized gains	318				318				239
Gross unrealized losses	3				3				2
Fair value	820				820				728
Available-for-Sale Securities Scheduled Maturity Dates of Debt Securities (Details) [Abstract]
Amortized cost - maturity less than 1 year	6				6
Amortized cost - maturity between 1 and 5 years	92				92
Amortized cost - maturity between 6 and 10 years	56				56
Amortized cost - maturity in excess of 10 years	74				74
Amortized cost total	228				228
Fair value - maturity less than 1 year	6				6
Fair value - maturity between 1 and 5 years	96				96
Fair value - maturity between 6 and 10 years	58				58
Fair value - maturity in excess of 10 years	76				76
Fair value total	236				236
Available-for-Sale Securities Proceeds From and Realized Gains and Losses (Details) [Abstract]
Proceeds from sales of NDT securities	33	[1]	23	[1]	92		102
Other proceeds from sales							3
Gross realized gains	3	[2]	2	[2]	10	[2]	15	[2]
Gross realized losses	2	[2]	2	[2]	6	[2]	8	[2]
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	488				488				474
Gross unrealized gains	318				318				239
Gross unrealized losses	2				2				1
Fair value	804				804				712
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | Cash And Cash Equivalents [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	14				14				11
Gross unrealized gains
Gross unrealized losses
Fair value	14				14				11
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | United States Large Cap Equity Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	230				230				222
Gross unrealized gains	264				264				190
Gross unrealized losses
Fair value	494				494				412
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | United States Mid Small Cap Equity Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	31				31				30
Gross unrealized gains	43				43				30
Gross unrealized losses
Fair value	74				74				60
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | United States Treasury Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	90				90				86
Gross unrealized gains	6				6				9
Gross unrealized losses
Fair value	96				96				95
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | United States Government Sponsored Agency Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	5				5				8
Gross unrealized gains	1				1				1
Gross unrealized losses
Fair value	6				6				9
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | Municipality Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	74				74				78
Gross unrealized gains	2				2				5
Gross unrealized losses	1				1				1
Fair value	75				75				82
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | Investment Grade Corporate Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	39				39				36
Gross unrealized gains	2				2				4
Gross unrealized losses	1				1
Fair value	40				40				40
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | Other Debt Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	3				3				3
Gross unrealized gains
Gross unrealized losses
Fair value	3				3				3
PPL Energy Supply LLC [Member] | Nuclear Decommissioning Trust Funds [Member] | Receivables Payables Net [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	2				2
Gross unrealized gains
Gross unrealized losses
Fair value	2				2
PPL Energy Supply LLC [Member] | Auction Rate Securities [Member]
Available-for-Sale Securities Balance Sheet (Details) [Abstract]
Amortized cost	17				17				17
Gross unrealized gains
Gross unrealized losses	1				1				1
Fair value	$ 16				$ 16				$ 16

[1] These proceeds are used to pay income taxes and fees related to managing the trust. Remaining proceeds are reinvested in the trust.

[2] Excludes the impact of other-than-temporary impairment charges recognized on the Statements of Income.