Goodwill and Other Intangible Assets (Other Intangibles) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Subject to amortization: [Abstract]
Gross carrying amount	$ 1,062		$ 1,060
Accumulated amortization	396		364
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	266		255
Gross carrying amount - other intangible assets	1,328		1,315
Land And Transmission Rights [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	16		16
Easements [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	250		239
Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	408	[1]	408	[1]
Accumulated amortization	250		202
Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	359		331
Accumulated amortization	121		117
Emission Allowances And Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Gross carrying amount	15	[2]	16	[2]
Accumulated amortization	0		0
Amortization expense	24		23		12
Licenses And Other [Member]
Subject to amortization: [Abstract]
Gross carrying amount	280	[3]	305	[3]
Accumulated amortization	25	[3]	45	[3]
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	57		61		61
Forecasted amortization in 2015	58
Forecasted amortization in 2016	34
Forecasted amortization in 2017	17
Forecasted amortization in 2018	17
Forecasted amortization in 2019	17
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	47		51		47
Forecasted amortization in 2015	50
Forecasted amortization in 2016	26
Forecasted amortization in 2017	9
Forecasted amortization in 2018	9
Forecasted amortization in 2019	9
Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With No Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	10		10		14
Forecasted amortization in 2015	8
Forecasted amortization in 2016	8
Forecasted amortization in 2017	8
Forecasted amortization in 2018	8
Forecasted amortization in 2019	8
PPL Energy Supply LLC [Member]
Subject to amortization: [Abstract]
Gross carrying amount	297		323
Accumulated amortization	33		53
PPL Energy Supply LLC [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	17		17
Accumulated amortization	14		14
PPL Energy Supply LLC [Member] | Emission Allowances And Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Gross carrying amount	10	[2]	11	[2]
Accumulated amortization	0		0
Amortization expense	24		23		12
PPL Energy Supply LLC [Member] | Licenses And Other [Member]
Subject to amortization: [Abstract]
Gross carrying amount	270	[3]	295	[3]
Accumulated amortization	19	[3]	39	[3]
PPL Energy Supply LLC [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	4		5		9
PPL Electric Utilities Corp [Member]
Subject to amortization: [Abstract]
Gross carrying amount	325		298
Accumulated amortization	106		103
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount - other intangible assets	341		314
PPL Electric Utilities Corp [Member] | Land And Transmission Rights [Member]
Not subject to amortization due to indefinite life: [Line Items]
Gross carrying amount	16		16
PPL Electric Utilities Corp [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	321		293
Accumulated amortization	105		102
PPL Electric Utilities Corp [Member] | Licenses And Other [Member]
Subject to amortization: [Abstract]
Gross carrying amount	4		5
Accumulated amortization	1		1
LG And E And KU Energy LLC [Member]
Subject to amortization: [Abstract]
Gross carrying amount	419		419
Accumulated amortization	245		198
LG And E And KU Energy LLC [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	269	[4]	269	[4]
Accumulated amortization	210	[4]	171	[4]
LG And E And KU Energy LLC [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	21		20
Accumulated amortization	2		2
LG And E And KU Energy LLC [Member] | Emission Allowances [Member]
Subject to amortization: [Abstract]
Gross carrying amount	3	[2]	4	[2]
Accumulated amortization	0		0
LG And E And KU Energy LLC [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	126	[5]	126	[5]
Accumulated amortization	33		25
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	47		52		47
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	47		51		47
Forecasted amortization in 2015	50
Forecasted amortization in 2016	26
Forecasted amortization in 2017	9
Forecasted amortization in 2018	9
Forecasted amortization in 2019	9
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
Louisville Gas And Electric Co [Member]
Subject to amortization: [Abstract]
Gross carrying amount	219		219
Accumulated amortization	122		99
Louisville Gas And Electric Co [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	124	[4]	124	[4]
Accumulated amortization	98	[4]	81	[4]
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] | Emission Allowances [Member]
Subject to amortization: [Abstract]
Gross carrying amount	1		1
Accumulated amortization	0		0
Louisville Gas And Electric Co [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	87	[5]	87	[5]
Accumulated amortization	23		17
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	23		23		23
Forecasted amortization in 2015	24
Forecasted amortization in 2016	13
Forecasted amortization in 2017	6
Forecasted amortization in 2018	6
Forecasted amortization in 2019	6
Kentucky Utilities Co [Member]
Subject to amortization: [Abstract]
Gross carrying amount	200		200
Accumulated amortization	123		99
Kentucky Utilities Co [Member] | Coal Contracts [Member]
Subject to amortization: [Abstract]
Gross carrying amount	145	[4]	145	[4]
Accumulated amortization	112	[4]	90	[4]
Kentucky Utilities Co [Member] | Land And Transmission Rights [Member]
Subject to amortization: [Abstract]
Gross carrying amount	14		13
Accumulated amortization	1		1
Kentucky Utilities Co [Member] | Emission Allowances [Member]
Subject to amortization: [Abstract]
Gross carrying amount	2	[2]	3	[2]
Accumulated amortization	0		0
Kentucky Utilities Co [Member] | Ohio Valley Electric Corporation Power Purchase Agreement [Member]
Subject to amortization: [Abstract]
Gross carrying amount	39	[5]	39	[5]
Accumulated amortization	10		8
Kentucky Utilities Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits [Member]
Subject to amortization: [Abstract]
Amortization expense	24		29		24
Kentucky Utilities Co [Member] | Other Intangibles Excluding Emission Allowances And Or Renewable Energy Credits With Regulatory Offset [Member]
Subject to amortization: [Abstract]
Amortization expense	24		28		24
Forecasted amortization in 2015	26
Forecasted amortization in 2016	13
Forecasted amortization in 2017	3
Forecasted amortization in 2018	3
Forecasted amortization in 2019	3
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

[1] Gross carrying amount includes the fair value at the acquisition date of the OVEC power purchase contract and coal contracts with terms favorable to market recognized as a result of the 2010 acquisition of LKE by PPL. Offsetting regulatory liabilities were recorded related to these contracts, which are being amortized over the same period as the intangible assets, eliminating any income statement impact. This is referred to as "regulatory offset" in the tables below. See Note 6 for additional information.

[2] Emission allowances/RECs are expensed when consumed or sold; therefore, there is no accumulated amortization.

[3] "Other" includes costs for the development of licenses, the most significant of which is the COLA. Amortization of these costs begins when the related asset is placed in service. See Note 8 for additional information on the COLA.

[4] Gross carrying amount represents the fair value at the acquisition date of coal contracts with terms favorable to market recognized as a result of the 2010 acquisition by PPL. An offsetting regulatory liability was recorded related to these contracts, which is being amortized over the same period as the intangible assets, eliminating any income statement impact. See Note 6 for additional information.

[5] Gross carrying amount represents the fair value at the acquisition date of the OVEC power purchase contract recognized as a result of the 2010 acquisition by PPL.An offsetting regulatory liability was recorded related to this contract, which is being amortized over the same period as the intangible asset, eliminating any income statement impact.See Note 6 for additional information.