Goodwill and Other Intangible Assets (Other Intangibles) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Subject to amortization: [Abstract]
Gross carrying amount	$ 528	$ 775
Accumulated amortization	190	442
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	359	367
Gross carrying amount - other intangible assets	887	1,142
Land And Transmission Rights [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	12	19
Easements [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	347	348
Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	138	405
Accumulated amortization	67	325
Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	382	362
Accumulated amortization	120	115
Emission Allowances And Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Gross carrying amount	1	2
Accumulated amortization	0	0
Licenses And Other [Member]
Subject to amortization: [Abstract]
Gross carrying amount	7	6
Accumulated amortization	3	2
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	15	30	$ 57
Forecasted amortization in 2018	15
Forecasted amortization in 2019	15
Forecasted amortization in 2020	14
Forecasted amortization in 2021	14
Forecasted amortization in 2022	14
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With No Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	6	6	6
Forecasted amortization in 2018	6
Forecasted amortization in 2019	6
Forecasted amortization in 2020	6
Forecasted amortization in 2021	6
Forecasted amortization in 2022	6
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	9	24	51
Forecasted amortization in 2018	9
Forecasted amortization in 2019	9
Forecasted amortization in 2020	8
Forecasted amortization in 2021	8
Forecasted amortization in 2022	8
PPL Electric Utilities Corp [Member]
Subject to amortization: [Abstract]
Gross carrying amount	364	344
Accumulated amortization	118	113
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount - other intangible assets	377	364
PPL Electric Utilities Corp [Member] | Land And Transmission Rights [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	13	20
PPL Electric Utilities Corp [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	361	341
Accumulated amortization	117	112
PPL Electric Utilities Corp [Member] | Licenses And Other [Member]
Subject to amortization: [Abstract]
Gross carrying amount	3	3
Accumulated amortization	1	1
LG And E And KU Energy LLC [Member]
Subject to amortization: [Abstract]
Gross carrying amount	147	416
Accumulated amortization	61	321
LG And E And KU Energy LLC [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	0	269
Accumulated amortization	0	269
LG And E And KU Energy LLC [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	21	21
Accumulated amortization	3	3
LG And E And KU Energy LLC [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	126	126
Accumulated amortization	58	49
LG And E And KU Energy LLC [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	9	25	51
LG And E And KU Energy LLC [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With No Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	0	1	0
LG And E And KU Energy LLC [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	9	24	51
Forecasted amortization in 2018	9
Forecasted amortization in 2019	9
Forecasted amortization in 2020	8
Forecasted amortization in 2021	8
Forecasted amortization in 2022	8
Louisville Gas And Electric Co [Member]
Subject to amortization: [Abstract]
Gross carrying amount	94	218
Accumulated amortization	41	159
Louisville Gas And Electric Co [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	0	124
Accumulated amortization	0	124
Louisville Gas And Electric Co [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	7	7
Accumulated amortization	1	1
Louisville Gas And Electric Co [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	87	87
Accumulated amortization	40	34
Louisville Gas And Electric Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	6	13	24
Forecasted amortization in 2018	6
Forecasted amortization in 2019	6
Forecasted amortization in 2020	6
Forecasted amortization in 2021	6
Forecasted amortization in 2022	6
Kentucky Utilities Co [Member]
Subject to amortization: [Abstract]
Gross carrying amount	53	198
Accumulated amortization	20	162
Kentucky Utilities Co [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	0	145
Accumulated amortization	0	145
Kentucky Utilities Co [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	14	14
Accumulated amortization	2	2
Kentucky Utilities Co [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	39	39
Accumulated amortization	18	15
Kentucky Utilities Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	3	12	27
Kentucky Utilities Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With No Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	0	1	0
Kentucky Utilities Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	3	$ 11	$ 27
Forecasted amortization in 2018	3
Forecasted amortization in 2019	3
Forecasted amortization in 2020	2
Forecasted amortization in 2021	2
Forecasted amortization in 2022	$ 2