Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Goodwill	$ 3,178	$ 3,198
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	915	815
Restricted Cash, Current	3	3
Restricted Cash, Noncurrent	18	18
Cash, Cash Equivalents and Restricted Cash	936	836	$ 540	$ 643
U.K. Regulated [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill	2,500	2,500
Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	34	30
Charged to Income	9
Deductions	5
Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	26	27
Charged to Income	0
Deductions	1
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	33	262
Restricted Cash, Current	2	2
Restricted Cash, Noncurrent	0	0
Cash, Cash Equivalents and Restricted Cash	35	264	25	269
PPL Electric Utilities Corp [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	28	25
Charged to Income	5
Deductions	2
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	47	27	22	24
LG And E And KU Energy LLC [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	2	2
Charged to Income	2
Deductions	2
LG And E And KU Energy LLC [Member] | Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	25	26
Charged to Income	0
Deductions	1
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	15	9	10
Louisville Gas And Electric Co [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	1	1
Charged to Income	1
Deductions	1
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	40	12	$ 13	$ 14
Kentucky Utilities Co [Member] | Accounts Receivable - Customer and Unbilled Revenue [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance	1	$ 1
Charged to Income	1
Deductions	$ 1