Segment and Related Information (Income Statement and Balance Sheet Data) (Details) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Integer		Dec. 31, 2018 USD ($)		Dec. 31, 2017 USD ($)
Income Statement Data
Operating Revenues from external customers		$ 1,954	$ 1,933	$ 1,803	$ 2,079	$ 1,939	$ 1,872	$ 1,848	$ 2,126	$ 7,769		$ 7,785		$ 7,447
Depreciation										1,199		1,094		1,008
Amortization										81		78		97
Unrealized (gains) losses on derivatives and other hedging activities										73		(186)		178
Interest Expense										994		963		901
Income Before Income Taxes										2,155		2,285		1,912
Income Taxes										409		458		784
Deferred income taxes and investment tax credits										309		355		707
Net income		364	475	441	466	415	445	515	452	1,746		1,827		1,128
Cash Flow Data
Expenditures for long-lived assets										3,107		3,268		3,171
Balance Sheet Data
Total Assets		45,680				43,396				$ 45,680		43,396
Segment Information (Numeric) [Abstract]
Number of reportable segments | Integer										3
U.K. Regulated [Member]
Income Statement Data
Operating Revenues from external customers										$ 2,167		2,268		2,091
Depreciation										250		247		230
Amortization										25		34		34
Unrealized (gains) losses on derivatives and other hedging activities										62		(190)		166
Interest Expense										405		413		397
Income Before Income Taxes										1,169		1,339		804
Income Taxes										192		225		152
Deferred income taxes and investment tax credits										140		118		66
Net income										977		1,114		652
Cash Flow Data
Expenditures for long-lived assets										857		954		1,015
Balance Sheet Data
Total Assets		17,622				16,700				17,622		16,700
Segment Information (Numeric) [Abstract]
Net property, plant and equipment not subject to accounting for the effects of certain types of regulation		13,200				12,400				13,200		12,400
Kentucky Regulated [Member]
Income Statement Data
Operating Revenues from external customers										3,206		3,214		3,156
Depreciation										547		475		439
Amortization										27		18		24
Unrealized (gains) losses on derivatives and other hedging activities										6		6		6
Interest Expense										298		274		261
Income Before Income Taxes										530		531		645
Income Taxes										94		120		359
Deferred income taxes and investment tax credits										82		94		294
Net income										436		411		286
Cash Flow Data
Expenditures for long-lived assets										1,097		1,117		892
Balance Sheet Data
Total Assets		15,597				15,078				15,597		15,078
Pennsylvania Regulated [Member]
Income Statement Data
Operating Revenues from external customers										2,358		2,277		2,195
Depreciation										386		352		309
Amortization										24		22		33
Interest Expense										169		159		142
Income Before Income Taxes										607		567		575
Income Taxes										149		136		216
Deferred income taxes and investment tax credits										90		125		257
Net income										458		431		359
Cash Flow Data
Expenditures for long-lived assets										1,121		1,196		1,254
Balance Sheet Data
Total Assets		11,918				11,257				11,918		11,257
Corporate And Other [Member]
Income Statement Data
Operating Revenues from external customers										38		26		5
Depreciation										16		20		30
Amortization										5		4		6
Unrealized (gains) losses on derivatives and other hedging activities										5		(2)		6
Interest Expense										122		117		101
Income Before Income Taxes										(151)		(152)		(112)
Income Taxes										(26)		(23)		57
Deferred income taxes and investment tax credits										(3)		18		90
Net income										(125)		(129)		(169)
Cash Flow Data
Expenditures for long-lived assets										32		1		10
Balance Sheet Data
Total Assets		543				361				543		361
PPL Electric Utilities Corp [Member]
Income Statement Data
Operating Revenues from external customers		602	590	521	645	573	548	517	639	2,358		2,277		2,195
Depreciation										386		352		309
Amortization										24		22		33
Interest Expense										170		159		142
Income Before Income Taxes										606		566		575
Income Taxes										149		136		213
Deferred income taxes and investment tax credits										90		125		258
Net income		124	$ 118	$ 94	$ 121	96	$ 111	$ 75	$ 148	457	[1]	430	[1]	362	[1]
Balance Sheet Data
Total Assets		11,901				11,243				$ 11,901		11,243
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										$ 3,206		3,214		3,156
Depreciation										547		475		439
Amortization										27		18		24
Interest Expense										226		206		197
Income Before Income Taxes										571		574		691
Income Taxes										103		129		375
Deferred income taxes and investment tax credits										82		94		294
Net income										468		445		316
Balance Sheet Data
Total Assets		15,931				15,412				$ 15,931		15,412
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										$ 1,500		1,496		1,453
Depreciation										231		195		183
Amortization										15		14		14
Interest Expense										87		76		71
Income Before Income Taxes										295		297		344
Income Taxes										63		64		131
Deferred income taxes and investment tax credits										56		60		126
Net income	[2]									232		233		213
Balance Sheet Data
Total Assets		7,133				6,883				$ 7,133		6,883
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										$ 1,740		1,760		1,744
Depreciation										315		279		255
Amortization										10		3		9
Interest Expense										109		100		96
Income Before Income Taxes										372		362		418
Income Taxes										79		76		159
Deferred income taxes and investment tax credits										39		48		152
Net income	[3]									293		286		$ 259
Balance Sheet Data
Total Assets		$ 8,825				$ 8,540				$ 8,825		$ 8,540
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 approximates comprehensive income.