Financing Activities - Distributions and Capital Contributions (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Feb. 28, 2022	Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Distributions [Line Items]
Current quarterly common stock dividend (in dollars per share)		$ 0.415	$ 1.66	$ 1.66	$ 1.65
Annualized current quarterly common stock dividend (in dollars per share)		$ 1.66
Deferred Interest Payment			$ 0
Subsequent Event [Member]
Distributions [Line Items]
Current quarterly common stock dividend (in dollars per share)	$ 0.20
Louisville Gas And Electric Co [Member]
Distributions [Line Items]
Restricted net assets at end of period			1,400
Unrestricted assets at the end of period			$ 1,700
Minimum adjusted equity to total capitalization in order to pay dividends			30.00%
Kentucky Utilities Co [Member]
Distributions [Line Items]
Restricted net assets at end of period			$ 1,900
Unrestricted assets at the end of period			$ 2,000
Minimum adjusted equity to total capitalization in order to pay dividends			30.00%