Jointly Owned Facilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Trimble County Unit 1 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	75.00%	75.00%
Electric plant	$ 464	$ 455
Accumulated depreciation	110	94
Construction work in progress	$ 0	$ 1
Trimble County Unit 2 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	75.00%	75.00%
Electric plant	$ 1,490	$ 1,372
Accumulated depreciation	300	276
Construction work in progress	$ 49	$ 148
Louisville Gas And Electric Co [Member] | E W Brown Units 6 And 7 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	38.00%	38.00%
Electric plant	$ 53	$ 53
Accumulated depreciation	27	25
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Paddys Run Unit 13 And E W Brown Unit 5 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	53.00%	53.00%
Electric plant	$ 52	$ 51
Accumulated depreciation	29	27
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Trimble County Unit 1 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	75.00%	75.00%
Electric plant	$ 464	$ 455
Accumulated depreciation	110	94
Construction work in progress	$ 0	$ 1
Louisville Gas And Electric Co [Member] | Trimble County Unit 2 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	14.25%	14.25%
Electric plant	$ 447	$ 384
Accumulated depreciation	74	66
Construction work in progress	$ 25	$ 78
Louisville Gas And Electric Co [Member] | Trimble County Units 5 And 6 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	29.00%	29.00%
Electric plant	$ 37	$ 36
Accumulated depreciation	17	16
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Trimble County Units 7 Through 10 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	37.00%	37.00%
Electric plant	$ 82	$ 81
Accumulated depreciation	39	36
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Cane Run Unit 7 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	22.00%	22.00%
Electric plant	$ 127	$ 126
Accumulated depreciation	25	21
Construction work in progress	$ 3	$ 2
Louisville Gas And Electric Co [Member] | E W Brown Solar Unit [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	39.00%	39.00%
Electric plant	$ 10	$ 10
Accumulated depreciation	3	3
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Jointly Owned Solar Share [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	44.00%	44.00%
Electric plant	$ 3	$ 3
Accumulated depreciation	0	0
Construction work in progress	$ 0	$ 0
Louisville Gas And Electric Co [Member] | Jointly Owned Mercer Solar
Jointly Owned Facilities [Line Items]
Ownership interest	37.00%
Electric plant	$ 7
Accumulated depreciation	0
Construction work in progress	$ 0
Louisville Gas And Electric Co [Member] | Jointly Owned Mill Creek 5
Jointly Owned Facilities [Line Items]
Ownership interest	31.00%
Electric plant	$ 0
Accumulated depreciation	0
Construction work in progress	$ 2
Louisville Gas And Electric Co [Member] | Jointly Owned Brown Wind
Jointly Owned Facilities [Line Items]
Ownership interest	36.00%
Electric plant	$ 0
Accumulated depreciation	0
Construction work in progress	$ 0
Kentucky Utilities Co [Member] | E W Brown Units 6 And 7 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	62.00%	62.00%
Electric plant	$ 87	$ 87
Accumulated depreciation	45	42
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Paddys Run Unit 13 And E W Brown Unit 5 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	47.00%	47.00%
Electric plant	$ 46	$ 45
Accumulated depreciation	25	23
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Trimble County Unit 2 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	60.75%	60.75%
Electric plant	$ 1,043	$ 987
Accumulated depreciation	227	210
Construction work in progress	$ 24	$ 70
Kentucky Utilities Co [Member] | Trimble County Units 5 And 6 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	71.00%	71.00%
Electric plant	$ 86	$ 84
Accumulated depreciation	41	38
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Trimble County Units 7 Through 10 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	63.00%	63.00%
Electric plant	$ 135	$ 133
Accumulated depreciation	65	61
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Cane Run Unit 7 [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	78.00%	78.00%
Electric plant	$ 449	$ 446
Accumulated depreciation	90	77
Construction work in progress	$ 10	$ 6
Kentucky Utilities Co [Member] | E W Brown Solar Unit [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	61.00%	61.00%
Electric plant	$ 16	$ 16
Accumulated depreciation	5	5
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Jointly Owned Solar Share [Member]
Jointly Owned Facilities [Line Items]
Ownership interest	56.00%	56.00%
Electric plant	$ 4	$ 4
Accumulated depreciation	0	0
Construction work in progress	$ 0	$ 0
Kentucky Utilities Co [Member] | Jointly Owned Mercer Solar
Jointly Owned Facilities [Line Items]
Ownership interest	63.00%
Electric plant	$ 12
Accumulated depreciation	0
Construction work in progress	$ 1
Kentucky Utilities Co [Member] | Jointly Owned Mill Creek 5
Jointly Owned Facilities [Line Items]
Ownership interest	69.00%
Electric plant	$ 0
Accumulated depreciation	0
Construction work in progress	$ 3
Kentucky Utilities Co [Member] | Jointly Owned Brown Wind
Jointly Owned Facilities [Line Items]
Ownership interest	64.00%
Electric plant	$ 1
Accumulated depreciation	0
Construction work in progress	$ 0