Accounting Policies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) Integer	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2017 USD ($)
Utility Revenue (Details) [Abstract]
Operating Revenues	$ 7,607	$ 7,769	$ 7,785
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	708	815
Restricted cash - current	1	3
Restricted Cash - noncurrent	18	18
Total Cash, Cash Equivalents and Restricted Cash	727	836	643		$ 511
Property, Plant and Equipment (Numeric) [Abstract]
Interest costs, capitalized during the period	$ 9	10	15
Discount Rate Change For United Kingdom Pension Plans Numeric [Abstract]
Percentage in excess of gains and losses equal to the plan's projected benefit obligation to use accelerated amortization	30.00%
Minimum percentage of gains and losses under the accelerated method that are amortized on a straight line basis	10.00%
Maximum percentage of gains and losses under the accelerated that are amortized on a straight line basis	30.00%
Income Taxes [Abstract]
Minimum percentage to be attained of likelihood of uncertain tax position being realized	50.00%
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 361	332
Balance Sheet Classification of Deferred Taxes [Abstract]
Goodwill	3,274	3,198	$ 3,162
Fuel [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	95	106
Natural Gas Stored Underground [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	30	35
Material And Supplies [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 236	$ 191
Regulated Operations [Member] | Utility Plant [Member]
Depreciation (Details) [Abstract]
Weighted-average rates	2.81%	2.84%	2.77%
Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts (Details) [Roll Forward]
Balance at beginning of period	$ 58	$ 56	$ 51
Additions charged to income	31	37	41
Additions charged to other accounts	0	3	3
Deductions	16	38	39
Balance at end of period	$ 75	58	56
WPD [Member]
Summary of Significant Accounting Policies [Line Items]
Period of lag in reporting results for WPD (in months) | Integer	1
Revenue Recognition (Numeric) [Abstract]
Number of regulatory years later future demand revenue is affected	2 years
Percentage WPD's distribution network operators are able to retain of any under-spends	70.00%
Percentage WPD's distribution network operators bear of any over-spends	70.00%
Period of lag between incentives and penalties are reflected in customers' rates	2 years
Refunded/recovered period of lag for recovery of over and under-recovered amounts arising from 2014/15 onwards	2 years
Balance Sheet Classification of Deferred Taxes [Abstract]
Goodwill				$ 2,500
PPL Electric Utilities Corp [Member]
Utility Revenue (Details) [Abstract]
Operating Revenues	$ 2,331	2,358	2,277
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	40	262
Restricted cash - current	0	2
Restricted Cash - noncurrent	0	0
Total Cash, Cash Equivalents and Restricted Cash	40	264	269		51
Property, Plant and Equipment (Numeric) [Abstract]
Interest costs, capitalized during the period	$ 7	8	$ 7
Discount Rate Change For United Kingdom Pension Plans Numeric [Abstract]
Percentage in excess of gains and losses equal to the plan's projected benefit obligation to use accelerated amortization	30.00%
Minimum percentage of gains and losses under the accelerated method that are amortized on a straight line basis	10.00%
Maximum percentage of gains and losses under the accelerated that are amortized on a straight line basis	30.00%
Income Taxes [Abstract]
Minimum percentage to be attained of likelihood of uncertain tax position being realized	50.00%
Intercompany tax receivables (payables)	$ (9)	3
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	59	33
PPL Electric Utilities Corp [Member] | Fuel [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	0	0
PPL Electric Utilities Corp [Member] | Natural Gas Stored Underground [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	0	0
PPL Electric Utilities Corp [Member] | Material And Supplies [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 59	$ 33
PPL Electric Utilities Corp [Member] | Regulated Operations [Member] | Utility Plant [Member]
Depreciation (Details) [Abstract]
Weighted-average rates	2.99%	3.05%	3.01%
PPL Electric Utilities Corp [Member] | Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts (Details) [Roll Forward]
Balance at beginning of period	$ 28	$ 27	$ 24
Additions charged to income	19	26	29
Additions charged to other accounts	0	0	0
Deductions	8	25	26
Balance at end of period	41	28	27
LG And E And KU Energy LLC [Member]
Utility Revenue (Details) [Abstract]
Operating Revenues	3,106	3,206	3,214
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 29	27	$ 24		30
Discount Rate Change For United Kingdom Pension Plans Numeric [Abstract]
Percentage in excess of gains and losses equal to the plan's projected benefit obligation to use accelerated amortization	30.00%
Minimum percentage of gains and losses under the accelerated method that are amortized on a straight line basis	10.00%
Maximum percentage of gains and losses under the accelerated that are amortized on a straight line basis	30.00%
Income Taxes [Abstract]
Minimum percentage to be attained of likelihood of uncertain tax position being realized	50.00%
Intercompany tax receivables (payables)	$ (12)	(8)
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	242	250
Balance Sheet Classification of Deferred Taxes [Abstract]
Goodwill	996	996
LG And E And KU Energy LLC [Member] | Fuel [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	95	106
LG And E And KU Energy LLC [Member] | Natural Gas Stored Underground [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	30	35
LG And E And KU Energy LLC [Member] | Material And Supplies [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 117	$ 109
LG And E And KU Energy LLC [Member] | Regulated Operations [Member] | Utility Plant [Member]
Depreciation (Details) [Abstract]
Weighted-average rates	4.00%	3.96%	3.69%
LG And E And KU Energy LLC [Member] | Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts (Details) [Roll Forward]
Balance at beginning of period	$ 28	$ 27	$ 25
Additions charged to income	9	8	10
Additions charged to other accounts	0	3	3
Deductions	5	10	11
Balance at end of period	32	28	27
Louisville Gas And Electric Co [Member]
Utility Revenue (Details) [Abstract]
Operating Revenues	1,456	1,500	1,496
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 7	15	$ 10		15
Discount Rate Change For United Kingdom Pension Plans Numeric [Abstract]
Percentage in excess of gains and losses equal to the plan's projected benefit obligation to use accelerated amortization	30.00%
Minimum percentage of gains and losses under the accelerated method that are amortized on a straight line basis	10.00%
Maximum percentage of gains and losses under the accelerated that are amortized on a straight line basis	30.00%
Income Taxes [Abstract]
Minimum percentage to be attained of likelihood of uncertain tax position being realized	50.00%
Intercompany tax receivables (payables)	$ (1)	(4)
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	119	122
Balance Sheet Classification of Deferred Taxes [Abstract]
Goodwill	389	389
Louisville Gas And Electric Co [Member] | Fuel [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	38	43
Louisville Gas And Electric Co [Member] | Natural Gas Stored Underground [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	30	35
Louisville Gas And Electric Co [Member] | Material And Supplies [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 51	$ 44
Louisville Gas And Electric Co [Member] | Regulated Operations [Member] | Utility Plant [Member]
Depreciation (Details) [Abstract]
Weighted-average rates	4.00%	3.87%	3.63%
Louisville Gas And Electric Co [Member] | Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts (Details) [Roll Forward]
Balance at beginning of period	$ 1	$ 1	$ 1
Additions charged to income	4	2	4
Additions charged to other accounts	0	2	1
Deductions	2	4	5
Balance at end of period	3	1	1
Kentucky Utilities Co [Member]
Utility Revenue (Details) [Abstract]
Operating Revenues	1,690	1,740	1,760
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 22	12	$ 14		$ 15
Discount Rate Change For United Kingdom Pension Plans Numeric [Abstract]
Percentage in excess of gains and losses equal to the plan's projected benefit obligation to use accelerated amortization	30.00%
Minimum percentage of gains and losses under the accelerated method that are amortized on a straight line basis	10.00%
Maximum percentage of gains and losses under the accelerated that are amortized on a straight line basis	30.00%
Income Taxes [Abstract]
Minimum percentage to be attained of likelihood of uncertain tax position being realized	50.00%
Intercompany tax receivables (payables)	$ (5)	(6)
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	123	128
Balance Sheet Classification of Deferred Taxes [Abstract]
Goodwill	607	607
Kentucky Utilities Co [Member] | Fuel [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	57	63
Kentucky Utilities Co [Member] | Natural Gas Stored Underground [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	0	0
Kentucky Utilities Co [Member] | Material And Supplies [Member]
Fuel, Materials and Supplies (Details) [Abstract]
Fuel, materials and supplies on the Balance Sheet	$ 66	$ 65
Kentucky Utilities Co [Member] | Regulated Operations [Member] | Utility Plant [Member]
Depreciation (Details) [Abstract]
Weighted-average rates	4.00%	4.02%	3.74%
Kentucky Utilities Co [Member] | Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts (Details) [Roll Forward]
Balance at beginning of period	$ 1	$ 2	$ 1
Additions charged to income	4	4	5
Additions charged to other accounts	0	1	2
Deductions	3	6	6
Balance at end of period	$ 2	$ 1	$ 2