Utility Rate Regulation (Regulatory Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Regulatory Assets [Line Items]
Current Regulatory Assets	$ 67	$ 36
Noncurrent Regulatory Assets	1,492	1,673
Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	8	12
Smart meter rider [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	13	11
Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	32	10
Transmission Formula Rate [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	0
Transmission Service Charge [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	10	0
Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	4	3
Noncurrent Regulatory Assets	4	10
Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	800	963
Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	39	56
Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	41	45
Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	22	20
Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	81	87
Accumulated cost of removal of utility plant [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	220	200
AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	279	273
Act 129 compliance rider [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	6	19
PPL Electric Utilities Corp [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	26	11
Noncurrent Regulatory Assets	726	824
PPL Electric Utilities Corp [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	0
PPL Electric Utilities Corp [Member] | Smart meter rider [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	13	11
PPL Electric Utilities Corp [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	0
PPL Electric Utilities Corp [Member] | Transmission Formula Rate [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	3	0
PPL Electric Utilities Corp [Member] | Transmission Service Charge [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	10	0
PPL Electric Utilities Corp [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	0
Noncurrent Regulatory Assets	0	3
PPL Electric Utilities Corp [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	467	558
PPL Electric Utilities Corp [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	15	22
PPL Electric Utilities Corp [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	18	22
PPL Electric Utilities Corp [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	0	0
PPL Electric Utilities Corp [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	0	0
PPL Electric Utilities Corp [Member] | Accumulated cost of removal of utility plant [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	220	200
PPL Electric Utilities Corp [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	0	0
PPL Electric Utilities Corp [Member] | Act 129 compliance rider [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	6	19
LG And E And KU Energy LLC [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	41	25
Noncurrent Regulatory Assets	766	849
LG And E And KU Energy LLC [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	8	12
LG And E And KU Energy LLC [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	32	10
LG And E And KU Energy LLC [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	1	3
Noncurrent Regulatory Assets	4	7
LG And E And KU Energy LLC [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	333	405
LG And E And KU Energy LLC [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	24	34
LG And E And KU Energy LLC [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	23	23
LG And E And KU Energy LLC [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	22	20
LG And E And KU Energy LLC [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	81	87
LG And E And KU Energy LLC [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	279	273
Louisville Gas And Electric Co [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	25	21
Noncurrent Regulatory Assets	380	431
Louisville Gas And Electric Co [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	8	12
Louisville Gas And Electric Co [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	16	7
Louisville Gas And Electric Co [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	1	2
Noncurrent Regulatory Assets	1	1
Louisville Gas And Electric Co [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	206	249
Louisville Gas And Electric Co [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	14	20
Louisville Gas And Electric Co [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	14	15
Louisville Gas And Electric Co [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	22	20
Louisville Gas And Electric Co [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	47	51
Louisville Gas And Electric Co [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	76	75
Kentucky Utilities Co [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	16	4
Noncurrent Regulatory Assets	386	418
Kentucky Utilities Co [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	0
Kentucky Utilities Co [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	16	3
Kentucky Utilities Co [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	1
Noncurrent Regulatory Assets	3	6
Kentucky Utilities Co [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	127	156
Kentucky Utilities Co [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	10	14
Kentucky Utilities Co [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	9	8
Kentucky Utilities Co [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	0	0
Kentucky Utilities Co [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	34	36
Kentucky Utilities Co [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	$ 203	$ 198