Defined Benefits (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2016		Jun. 30, 2015	Jun. 30, 2016		Jun. 30, 2015
Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost		$ 16		$ 26	$ 33		$ 56
Interest cost		44		52	87		110
Expected return on plan assets		(58)		(69)	(114)		(145)
Amortization of: [Abstract]
Prior service cost		3		2	4		4
Actuarial loss		10		22	25		47
Net periodic defined benefit costs (credits)	[1]	15		33	35		72
Net period defined benefit costs reflected in discontinued operations allocated from PPL's plans to PPL Energy Supply prior to the spinoff				7			18
Pension Benefits United Kingdom [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost		18	[2]	19	36	[2]	39
Interest cost		62	[2]	77	124	[2]	156
Expected return on plan assets		(132)	[2]	(129)	(265)	[2]	(260)
Amortization of: [Abstract]
Actuarial loss		36	[2]	40	73	[2]	79
Net periodic defined benefit costs (credits)	[1]	(16)	[2]	7	(32)	[2]	14
Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost		2		3	4		7
Interest cost		7		7	13		14
Expected return on plan assets		(6)		(7)	(11)		(14)
Amortization of: [Abstract]
Net periodic defined benefit costs (credits)		3		3	6		7
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		5		8	11		16
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost		6		6	12		13
Interest cost		18		17	35		34
Expected return on plan assets		(24)		(22)	(45)		(44)
Amortization of: [Abstract]
Prior service cost		3		2	4		4
Actuarial loss		5		9	10		17
Net periodic defined benefit costs (credits)		8		12	16		24
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		2	2		3
Interest cost		3		3	5		5
Expected return on plan assets		(1)		(2)	(3)		(3)
Amortization of: [Abstract]
Prior service cost		0		0	1		1
Net periodic defined benefit costs (credits)		3		3	5		6
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		4	5		7
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost		1		1	1		1
Interest cost		4		4	7		7
Expected return on plan assets		(5)		(5)	(10)		(10)
Amortization of: [Abstract]
Prior service cost		1		0	2		1
Actuarial loss		1		3	3		6
Net periodic defined benefit costs (credits)		2		3	3		5
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		$ 3		$ 4	$ 6		$ 9

[1] For the three and six months ended June 30, 2015, the total net periodic defined benefit cost includes $7 million and $18 million reflected in discontinued operations related to costs allocated from PPL's plans to PPL Energy Supply prior to the spinoff.

[2] See Note 2 for a discussion of changes to the discount rate used for the U.K. Pension Plans.