Segment and Related Information (Income Statement and Balance Sheet Data) (Details) $ in Millions		12 Months Ended
		Dec. 31, 2020 USD ($) Integer	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Income Statement Data
Operating Revenues from external customers		$ 7,607	$ 7,769	$ 7,785
Depreciation		1,287	1,199	1,094
Amortization		72	81	78
Unrealized (gains) losses on derivatives and other hedging activities		280	73	(186)
Interest Expense		1,001	994	963
Income Before Income Taxes		1,971	2,155	2,285
Income Taxes		502	409	458
Deferred income taxes and investment tax credits		402	309	355
Net income		1,469	1,746	1,827
Cash Flow Data
Expenditures for long-lived assets		3,273	3,107	3,268
Balance Sheet Data
Total Assets		$ 48,116	45,680
Segment Information (Numeric) [Abstract]
Number of reportable segments | Integer		3
U.K. Regulated [Member]
Income Statement Data
Operating Revenues from external customers		$ 2,133	2,167	2,268
Depreciation		265	250	247
Amortization		16	25	34
Unrealized (gains) losses on derivatives and other hedging activities		271	62	(190)
Interest Expense		400	405	413
Income Before Income Taxes		958	1,169	1,339
Income Taxes		272	192	225
Deferred income taxes and investment tax credits		233	140	118
Net income		686	977	1,114
Cash Flow Data
Expenditures for long-lived assets		995	857	954
Balance Sheet Data
Total Assets		19,094	17,622
Segment Information (Numeric) [Abstract]
Net property, plant and equipment not subject to accounting for the effects of certain types of regulation		14,400	13,200
Kentucky Regulated [Member]
Income Statement Data
Operating Revenues from external customers		3,106	3,206	3,214
Depreciation		606	547	475
Amortization		19	27	18
Unrealized (gains) losses on derivatives and other hedging activities		5	6	6
Interest Expense		300	298	274
Income Before Income Taxes		516	530	531
Income Taxes		98	94	120
Deferred income taxes and investment tax credits		64	82	94
Net income		418	436	411
Cash Flow Data
Expenditures for long-lived assets		966	1,097	1,117
Balance Sheet Data
Total Assets		15,943	15,597
Pennsylvania Regulated [Member]
Income Statement Data
Operating Revenues from external customers		2,330	2,358	2,277
Depreciation		403	386	352
Amortization		26	24	22
Interest Expense		172	169	159
Income Before Income Taxes		664	607	567
Income Taxes		167	149	136
Deferred income taxes and investment tax credits		82	90	125
Net income		497	458	431
Cash Flow Data
Expenditures for long-lived assets		1,154	1,121	1,196
Balance Sheet Data
Total Assets		12,347	11,918
Corporate And Other [Member]
Income Statement Data
Operating Revenues from external customers		38	38	26
Depreciation		13	16	20
Amortization		11	5	4
Unrealized (gains) losses on derivatives and other hedging activities		4	5	(2)
Interest Expense		129	122	117
Income Before Income Taxes		(167)	(151)	(152)
Income Taxes		(35)	(26)	(23)
Deferred income taxes and investment tax credits		23	(3)	18
Net income		(132)	(125)	(129)
Cash Flow Data
Expenditures for long-lived assets		158	32	1
Balance Sheet Data
Total Assets		732	543
PPL Electric Utilities Corp [Member]
Income Statement Data
Operating Revenues from external customers		2,331	2,358	2,277
Depreciation		403	386	352
Amortization		26	24	22
Interest Expense		173	170	159
Income Before Income Taxes		664	606	566
Income Taxes		167	149	136
Deferred income taxes and investment tax credits		83	90	125
Net income	[1]	497	457	430
Balance Sheet Data
Total Assets		$ 12,324	11,901
Segment Information (Numeric) [Abstract]
Number of operating segments | Integer		2
Number of reportable segments | Integer		1
LG And E And KU Energy LLC [Member]
Income Statement Data
Operating Revenues from external customers		$ 3,106	3,206	3,214
Depreciation		606	547	475
Amortization		19	27	18
Interest Expense		223	226	206
Income Before Income Taxes		556	571	574
Income Taxes		106	103	129
Deferred income taxes and investment tax credits		64	82	94
Net income		450	468	445
Balance Sheet Data
Total Assets		$ 16,277	15,931
Segment Information (Numeric) [Abstract]
Number of operating segments | Integer		1
Number of reportable segments | Integer		1
Louisville Gas And Electric Co [Member]
Income Statement Data
Operating Revenues from external customers		$ 1,456	1,500	1,496
Depreciation		259	231	195
Amortization		9	15	14
Interest Expense		87	87	76
Income Before Income Taxes		306	295	297
Income Taxes		62	63	64
Deferred income taxes and investment tax credits		3	56	60
Net income	[2]	244	232	233
Balance Sheet Data
Total Assets		$ 7,345	7,133
Segment Information (Numeric) [Abstract]
Number of operating segments | Integer		1
Number of reportable segments | Integer		1
Kentucky Utilities Co [Member]
Income Statement Data
Operating Revenues from external customers		$ 1,690	1,740	1,760
Depreciation		346	315	279
Amortization		8	10	3
Interest Expense		113	109	100
Income Before Income Taxes		343	372	362
Income Taxes		63	79	76
Deferred income taxes and investment tax credits		20	39	48
Net income	[3]	280	293	$ 286
Balance Sheet Data
Total Assets		$ 9,072	$ 8,825
Segment Information (Numeric) [Abstract]
Number of operating segments | Integer		1
Number of reportable segments | Integer		1

[1] Net income equals comprehensive income.

[2] Net income equals comprehensive income.

[3] Net income equals comprehensive income.