Derivative Instruments and Hedging Activities - Fair Values (Details) - Not Designated As Hedging Instruments [Member] - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Fair Values by Balance Sheet Location [Abstract]
Asset value	$ 59	$ 0
Liability value	14	18
Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	46	0
Other current liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	1	1
Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	13	0
Price risk management assets, noncurrent [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Other deferred credits and noncurrent liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	9	17
Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	1
Price risk management assets, current [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	10	17
Louisville Gas And Electric Co [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Liability value	10	18
Louisville Gas And Electric Co [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	1	1
Louisville Gas And Electric Co [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	1	1
Louisville Gas And Electric Co [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	9	17
Louisville Gas And Electric Co [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	$ 9	$ 17