Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Goodwill	$ 716	$ 716
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	421	442
Restricted Cash, Current	1	1
Cash, Cash Equivalents and Restricted Cash	422	443	$ 737	$ 660
Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	45	44
Charged to Income	2
Deductions	1
Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	28	28
Charged to Income	0
Deductions	0
PPL Electric Utilities Corp [Member]
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	29	40
Cash, Cash Equivalents and Restricted Cash	29	40	35	264
PPL Electric Utilities Corp [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	40	39
Charged to Income	1
Deductions	0
PPL Electric Utilities Corp [Member] | Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	1	1
Charged to Income	0
Deductions	0
LG And E And KU Energy LLC [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill	996	996
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	16	29	47	27
LG And E And KU Energy LLC [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	5	5
Charged to Income	1
Deductions	1
LG And E And KU Energy LLC [Member] | Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	27	27
Charged to Income	0
Deductions	0
Louisville Gas And Electric Co [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill	389	389
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	7	7	7	15
Louisville Gas And Electric Co [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	3	3
Charged to Income	0
Deductions	0
Kentucky Utilities Co [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill	607	607
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	8	22	$ 40	$ 12
Kentucky Utilities Co [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	2	$ 2
Charged to Income	1
Deductions	$ 1