Derivative Instruments and Hedging Activities (Commodity Volumes) (Details)	Jun. 30, 2013 MWh
Sales Contracts [Member] | Power [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	20,132,552	[1],[2]
Sales Contracts [Member] | Power [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	28,846,530	[1]
Sales Contracts [Member] | Power [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,693,573	[1]
Sales Contracts [Member] | Capacity [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	10,339	[1],[2]
Sales Contracts [Member] | Capacity [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	9,075	[1]
Sales Contracts [Member] | Capacity [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,453	[1]
Sales Contracts [Member] | Gas [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	2,395,839	[1]
Sales Contracts [Member] | Gas [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,919,285	[1]
Sales Contracts [Member] | Gas [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,210,551	[1]
Sales Contracts [Member] | Oil [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	148,614	[1],[2]
Purchase Contracts [Member] | Power [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,575,123	[1]
Purchase Contracts [Member] | Capacity [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	490	[1]
Purchase Contracts [Member] | Gas [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	27,768,152	[1],[2]
Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,807	[1],[2]
Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,519	[1]
Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,465	[1]
Purchase Contracts [Member] | Oil [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	300,000	[1]
Purchase Contracts [Member] | Oil [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	392,331	[1]
Purchase Contracts [Member] | Oil [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	378,315	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Power [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	20,132,552	[1],[2]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Power [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	28,846,530	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Power [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,693,573	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Capacity [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	10,339	[1],[2]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Capacity [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	9,075	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Capacity [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,453	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Gas [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	2,395,839	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Gas [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,919,285	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Gas [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,210,551	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Oil [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	148,614	[1],[2]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Power [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,575,123	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Capacity [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	490	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Gas [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	27,768,152	[1],[2]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2013 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,807	[1],[2]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,519	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	1,465	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | 2014 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	300,000	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	392,331	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	378,315	[1]

[1] Volumes for option contracts factor in the probability of an option being exercised and may be less than the notional amount of the option.

[2] Represents balance of the current year.