Leases - Lessee (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Lease, Cost [Abstract]
Operating lease cost	$ 20	$ 24	$ 28
Short-term lease cost	6	6	7
Total lease cost	26	30	35
Operating cash flows from operating leases	26	23	24
Right-of-use asset obtained in exchange for new operating lease liabilities	15	12	17
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2022	24
2023	17
2024	12
2025	5
2026	4
Thereafter	7
Total	$ 69
Assets and Liabilities, Lessee [Abstract]
Weighted-average discount rate	3.10%
Weighted-average remaining lease term (in years)	4 years
Current lease liabilities	$ 22
Non-current lease liabilities	42
Right-of-use assets	$ 60
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other deferred credits and noncurrent liabilities
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets
Louisville Gas And Electric Co [Member]
Lease, Cost [Abstract]
Operating lease cost	$ 6	6	8
Short-term lease cost	1	1	1
Total lease cost	7	7	9
Operating cash flows from operating leases	8	6	7
Right-of-use asset obtained in exchange for new operating lease liabilities	4	4	6
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2022	6
2023	5
2024	3
2025	1
2026	1
Thereafter	0
Total	$ 16
Assets and Liabilities, Lessee [Abstract]
Weighted-average discount rate	3.17%
Weighted-average remaining lease term (in years)	3 years
Current lease liabilities	$ 6
Non-current lease liabilities	9
Right-of-use assets	$ 13
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other deferred credits and noncurrent liabilities
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets
Louisville Gas And Electric Co [Member] | Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	1 year
Louisville Gas And Electric Co [Member] | Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	10 years
Kentucky Utilities Co [Member]
Lease, Cost [Abstract]
Operating lease cost	$ 9	10	13
Short-term lease cost	2	1	1
Total lease cost	11	11	14
Operating cash flows from operating leases	12	10	11
Right-of-use asset obtained in exchange for new operating lease liabilities	5	$ 7	$ 9
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2022	9
2023	7
2024	4
2025	1
2026	0
Thereafter	0
Total	$ 21
Assets and Liabilities, Lessee [Abstract]
Weighted-average discount rate	3.40%
Weighted-average remaining lease term (in years)	3 years
Current lease liabilities	$ 8
Non-current lease liabilities	12
Right-of-use assets	$ 19
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other deferred credits and noncurrent liabilities
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets
Kentucky Utilities Co [Member] | Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	1 year
Kentucky Utilities Co [Member] | Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	10 years