Utility Rate Regulation (Regulatory Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Regulatory Assets [Line Items]
Current Regulatory Assets	$ 99	$ 67
Noncurrent Regulatory Assets	1,262	1,492
Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	4	8
Smart meter rider [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	17	13
Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	46	32
Transmission Formula Rate [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	15	3
Transmission Service Charge [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	10
Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	10	1
Noncurrent Regulatory Assets	7	4
Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	570	800
Storm costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	7	0
Noncurrent Regulatory Assets	17	39
Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	30	41
Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	23	22
Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	75	81
Accumulated cost of removal of utility plant [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	240	220
AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	300	279
Act 129 compliance rider [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	0	6
PPL Electric Utilities Corp [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	40	26
Noncurrent Regulatory Assets	541	726
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	17	13
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	15	3
PPL Electric Utilities Corp [Member] | Transmission Service Charge [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	0	10
PPL Electric Utilities Corp [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	1	0
Noncurrent Regulatory Assets	3	0
PPL Electric Utilities Corp [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	290	467
PPL Electric Utilities Corp [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	7	0
Noncurrent Regulatory Assets	0	15
PPL Electric Utilities Corp [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	8	18
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	240	220
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	0	6
LG And E And KU Energy LLC [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	59	41
Noncurrent Regulatory Assets	721	766
LG And E And KU Energy LLC [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	4	8
LG And E And KU Energy LLC [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	46	32
LG And E And KU Energy LLC [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	9	1
Noncurrent Regulatory Assets	4	4
LG And E And KU Energy LLC [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	280	333
LG And E And KU Energy LLC [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	17	24
LG And E And KU Energy LLC [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	22	23
LG And E And KU Energy LLC [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	23	22
LG And E And KU Energy LLC [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	75	81
LG And E And KU Energy LLC [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	300	279
Louisville Gas And Electric Co [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	23	25
Noncurrent Regulatory Assets	351	380
Louisville Gas And Electric Co [Member] | Gas Supply Clause [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	4	8
Louisville Gas And Electric Co [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	12	16
Louisville Gas And Electric Co [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	7	1
Noncurrent Regulatory Assets	1	1
Louisville Gas And Electric Co [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	174	206
Louisville Gas And Electric Co [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	11	14
Louisville Gas And Electric Co [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	13	14
Louisville Gas And Electric Co [Member] | Interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	23	22
Louisville Gas And Electric Co [Member] | Terminated interest rate swaps [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	44	47
Louisville Gas And Electric Co [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	85	76
Kentucky Utilities Co [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	36	16
Noncurrent Regulatory Assets	370	386
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	34	16
Kentucky Utilities Co [Member] | Other [Member]
Regulatory Assets [Line Items]
Current Regulatory Assets	2	0
Noncurrent Regulatory Assets	3	3
Kentucky Utilities Co [Member] | Defined benefit plans [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	106	127
Kentucky Utilities Co [Member] | Storm costs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	6	10
Kentucky Utilities Co [Member] | Unamortized loss on debt [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	9	9
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	31	34
Kentucky Utilities Co [Member] | AROs [Member]
Regulatory Assets [Line Items]
Noncurrent Regulatory Assets	$ 215	$ 203