Derivative Instruments and Hedging Activities (Commodity Volumes Volumetric Activity) (Details)	Dec. 31, 2014 MWh
Purchase Contracts [Member] | Power [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	741,005	[1]
Purchase Contracts [Member] | Power [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	3,426,579	[1]
Purchase Contracts [Member] | Capacity [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	6	[1]
Purchase Contracts [Member] | Capacity [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	3	[1]
Purchase Contracts [Member] | Gas [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	136,349,655	[1]
Purchase Contracts [Member] | Gas [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	42,144,483	[1]
Purchase Contracts [Member] | Gas [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	5,804,511	[1]
Purchase Contracts [Member] | Gas [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,969,760	[1]
Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	2,803	[1]
Purchase Contracts [Member] | Oil [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	421,019	[1]
Purchase Contracts [Member] | Oil [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	374,334	[1]
Purchase Contracts [Member] | Oil [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	251,670	[1]
Purchase Contracts [Member] | Oil [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	60,000	[1]
Sales Contracts [Member] | Power [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	39,946,543	[1]
Sales Contracts [Member] | Power [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,999,532	[1]
Sales Contracts [Member] | Capacity [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	6,604	[1]
Sales Contracts [Member] | Capacity [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	249	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Power [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	741,005	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Power [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	3,426,579	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Capacity [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	6	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Capacity [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	3	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Gas [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	136,349,655	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Gas [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	42,144,483	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Gas [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	5,804,511	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Gas [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	8,969,760	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Financial Transmission Rights [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	2,803	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	421,019	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	374,334	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | 2017 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	251,670	[1]
PPL Energy Supply LLC [Member] | Purchase Contracts [Member] | Oil [Member] | Thereafter [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	60,000	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Power [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	39,946,543	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Power [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	4,999,532	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Capacity [Member] | 2015 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	6,604	[1]
PPL Energy Supply LLC [Member] | Sales Contracts [Member] | Capacity [Member] | 2016 [Member]
Commodity Volumetric Activity [Line Items]
Notional amount (in units)	249	[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.