Defined Benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Pension Plan [Member] | U.S.
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	$ 13	$ 13
Interest cost	38	41
Expected return on plan assets	(60)	(61)
Amortization of: [Abstract]
Prior service cost	2	2
Actuarial loss	20	13
Net Periodic Defined Benefit Costs (Credits) Prior To Settlements	13	8
Settlements	0	1
Net periodic defined benefit costs (credits)	13	9
Pension Plan [Member] | U.K.
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	23	17
Interest cost	36	47
Expected return on plan assets	(158)	(148)
Amortization of: [Abstract]
Prior service cost	0	0
Actuarial loss	54	24
Net Periodic Defined Benefit Costs (Credits) Prior To Settlements	(45)	(60)
Settlements	0	0
Net periodic defined benefit costs (credits)	(45)	(60)
Other Postretirement Benefits Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	2	1
Interest cost	5	6
Expected return on plan assets	(5)	(5)
Amortization of: [Abstract]
Net periodic defined benefit costs (credits)	2	2
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	3	3
LG And E And KU Energy LLC [Member] | Pension Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	5	6
Interest cost	16	16
Expected return on plan assets	(24)	(25)
Amortization of: [Abstract]
Prior service cost	2	2
Actuarial loss	9	4
Net periodic defined benefit costs (credits)	$ 8	$ 3
Regulatory Asset Amortization Period	15 years	15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period	$ 3
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	1	$ 1
Interest cost	2	2
Expected return on plan assets	(2)	(2)
Amortization of: [Abstract]
Net periodic defined benefit costs (credits)	1	1
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	1
Louisville Gas And Electric Co [Member] | Pension Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Interest cost		3
Expected return on plan assets		(6)
Amortization of: [Abstract]
Prior service cost		1
Actuarial loss		2
Net periodic defined benefit costs (credits)		0
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	$ 1	$ 0