Defined Benefits (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014		Sep. 30, 2015		Sep. 30, 2014
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Accrued pension obligations	$ 244			$ 244
Accrued postretirement obligation	7			$ 7
LGE [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
KU [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	20	$ 24		$ 76		$ 73
Interest cost	42	56		152		168
Expected return on plan assets	(56)	(72)		(201)		(216)
Amortization of:
Prior service cost	1	5		5		15
Actuarial (gain) loss	18	8		65		22
Net periodic defined benefit costs (credits) prior to termination benefits	25	21	[1]	97	[2]	62	[1]
Termination benefits	0	(7)	[3]	0		13	[3]
Net periodic defined benefit costs (credits)	25	14	[1]	97	[2]	75	[1]
Net period defined benefit costs reflected in discontinued operations allocated from PPL's plans to PPL Energy Supply prior to the spinoff		1		18		29
Pension Benefits United States [Member] | PPL Energy Supply LLC [Member]
Amortization of:
Termination benefits		(5)				11
Pension Benefits United States [Member] | PPL Electric [Member]
Amortization of:
Termination benefits		(2)				2
Pension Benefits United Kingdom [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	21	18		60		54
Interest cost	80	90		236		268
Expected return on plan assets	(133)	(133)		(393)		(395)
Amortization of:
Actuarial (gain) loss	39	34		118		100
Net periodic defined benefit costs (credits) prior to termination benefits	7	9		21		27
Net periodic defined benefit costs (credits)	7	9		21		27
Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	2	3		9		9
Interest cost	6	7		20		23
Expected return on plan assets	(6)	(6)		(20)		(19)
Amortization of:
Net periodic defined benefit costs (credits)	2	4		9		13
PPL Electric Utilities Corp [Member] | PPL Services [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	8	3	[4]	$ 24		18	[4]
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	7	5		$ 20		16
Interest cost	17	17		51		50
Expected return on plan assets	(22)	(21)		(66)		(62)
Amortization of:
Prior service cost	1	1		5		3
Actuarial (gain) loss	9	4		26		10
Net periodic defined benefit costs (credits)	12	6		36		17
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	1	1		4		3
Interest cost	2	2		7		7
Expected return on plan assets	(1)	(1)		(4)		(4)
Amortization of:
Prior service cost	1	1		2		2
Net periodic defined benefit costs (credits)	3	3		$ 9		8
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
Louisville Gas And Electric Co [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	3	2		$ 10		6
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	0	0		1		1
Interest cost	3	4		10		11
Expected return on plan assets	(5)	(4)		(15)		(14)
Amortization of:
Prior service cost	1	1		2		2
Actuarial (gain) loss	3	1		9		4
Net periodic defined benefit costs (credits)	2	2		$ 7		4
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member]
Net Periodic Defined Benefit Costs (Credits) (Numeric) [Abstract]
Number of years over which pension costs will be recovered				15 years
Kentucky Utilities Co [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	$ 4	$ 2		$ 13		$ 6

[1] For the three and nine months ended September 30, 2014 , the total net periodic defined benefit cost include s $ 1 million and $ 29 million reflected in d iscontinued o perations related to costs allocated from PPL's plans to PPL Energy Supply.

[2] For the nine months ended September 30, 2015 , the total net periodic defined benefit cost include s $ 18 million reflected in d iscontinued o perations related to costs allocated from PPL's plans to PPL Energy Supply prior to the spinoff .

[3] The three and nine months ended September 30, 2014 include termination benefits of $ (2) million and $ 2 million for PPL Electric . The remaining $ (5) million and $ 11 million relate to PPL Energy Supply and are reflected in d iscontinued o perations .

[4] The three and nine months ended September 30, 2014 include $ (2) million and $ 2 million of termination benefits for PPL Electric related to a one-time voluntary retirement window offered to certain bargaining unit employees.