Income and Other Taxes (Credit Carryforwards and Valuation Allowances and Reserves) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Credit carryforwards
Deferred tax asset tax credit carryforwards	$ 15	$ 401
Deferred Tax Assets, Valuation Allowances	462	536
Valuation Allowances and Reserves (Details) [Roll Forward]
Deferred Tax Assets, Valuation Allowances	462	536
Recycling Tax Credit [Member] | State [Member]
Credit carryforwards
Deferred tax asset tax credit carryforwards	14
Credit Carryforward Valuation Allowance Other	0
Other [Member] | State [Member]
Credit carryforwards
Deferred tax asset tax credit carryforwards	1
Credit Carryforward Valuation Allowance Other	0
Valuation Allowance Of Deferred Tax Assets [Member]
Valuation Allowances and Reserves (Details) [Roll Forward]
Balance at beginning of period	536	514	$ 495
Additions charged to income	48	26	24
Additions charged to other accounts	0	0	0
Deductions	122	4	5
Balance at end of period	462	536	$ 514
SEC Schedule 12-09, Valuation Allowance, Deduction, Business Disposition	113
Louisville Gas And Electric Co [Member]
Credit carryforwards
State tax credit carryforwards	11	12
Deferred Tax Assets, Valuation Allowances	11	12
Valuation Allowances and Reserves (Details) [Roll Forward]
Deferred Tax Assets, Valuation Allowances	11	12
Louisville Gas And Electric Co [Member] | Other [Member] | Federal [Member]
Credit carryforwards
State tax credit carryforwards	11
Deferred Tax Assets, Valuation Allowances	11
Valuation Allowances and Reserves (Details) [Roll Forward]
Deferred Tax Assets, Valuation Allowances	11
Kentucky Utilities Co [Member]
Credit carryforwards
State tax credit carryforwards	4	5
Deferred Tax Assets, Valuation Allowances	3	4
Valuation Allowances and Reserves (Details) [Roll Forward]
Deferred Tax Assets, Valuation Allowances	3	$ 4
Kentucky Utilities Co [Member] | Other [Member] | Federal [Member]
Credit carryforwards
State tax credit carryforwards	4
Deferred Tax Assets, Valuation Allowances	3
Valuation Allowances and Reserves (Details) [Roll Forward]
Deferred Tax Assets, Valuation Allowances	3
Kentucky Utilities Co [Member] | Other [Member] | Federal [Member] | Tax Credit Carryforward Expiration Year 2028 [Member]
Credit carryforwards
State tax credit carryforwards	3
Kentucky Utilities Co [Member] | Other [Member] | Federal [Member] | Tax Credit Carryforward Expiration Indefinite [Member]
Credit carryforwards
State tax credit carryforwards	$ 1