Segment and Related Information (Details) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Integer	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 1,512	$ 1,400	$ 4,298	$ 4,103
Net income (loss)		207	281	(1,614)	1,179
Balance Sheet Data [Abstract]
Assets		34,171		34,171		$ 48,116
Segment (Numeric) [Abstract]
Goodwill		716		716		716
Kentucky Regulated [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		879	806	2,505	2,331
Net income (loss)		159	129	389	330
Financing Costs Allocated to Segment, Net of Tax			8		25
Income Taxes Allocated to Segment			2		6
Balance Sheet Data [Abstract]
Assets		16,250		16,250		15,943
Pennsylvania Regulated [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		627	586	1,769	1,748
Net income (loss)		126	135	335	371
Balance Sheet Data [Abstract]
Assets		13,350		13,350		12,347
Corporate and Other [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		6	8	24	24
Net income (loss)		(76)	(147)	(848)	(227)
Balance Sheet Data [Abstract]
Assets		4,571		4,571		843
DiscontinuedOperationsSegment
Income Statement Data [Abstract]
Net income (loss)		(2)	164	(1,490)	705
Balance Sheet Data [Abstract]
Assets		0		0		18,983
PPL Electric Utilities Corp [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		627	586	1,769	1,748
Net income (loss)	[1]	126	134	335	370
Balance Sheet Data [Abstract]
Assets		13,320		$ 13,320		12,324
Segment (Numeric) [Abstract]
Number of Reportable Segments | Integer				1
Number of Operating Segments | Integer				2
Louisville Gas And Electric Co [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		395	363	$ 1,165	1,092
Net income (loss)	[2]	82	71	202	191
Balance Sheet Data [Abstract]
Assets		7,491		7,491		7,345
Segment (Numeric) [Abstract]
Goodwill		389		$ 389		389
Number of Reportable Segments | Integer				1
Number of Operating Segments | Integer				1
Kentucky Utilities Co [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		494	452	$ 1,374	1,272
Net income (loss)	[3]	99	$ 84	241	$ 217
Balance Sheet Data [Abstract]
Assets		9,188		9,188		9,072
Segment (Numeric) [Abstract]
Goodwill		$ 607		$ 607		$ 607
Number of Reportable Segments | Integer				1
Number of Operating Segments | Integer				1

[1] Net income equals comprehensive income.

[2] Net income equals comprehensive income.

[3] Net income equals comprehensive income.