Acquisitions, Development and Divestures (Details) $ in Millions		1 Months Ended				7 Months Ended	12 Months Ended
	Jun. 01, 2015 USD ($) shares	Jun. 30, 2016 USD ($) MW	Sep. 30, 2015 USD ($) coal-fired_unit	Jun. 30, 2015 USD ($) Integer coal-fired_unit	Mar. 31, 2015 coal-fired_unit	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($) kV Integer coal-fired_unit mi	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Continuing Involvement (Details) [Abstract]
Energy purchases							$ 685	$ 706	$ 855
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Results of Discontinued Operations (Details) [Abstract]
Income tax expense (benefit)							0	0	(30)
Loss from Discontinued Operations (net of income taxes)							$ 0	0	(921)
PPL Energy Supply Spinoff [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Spinoff agreement execution date				Jun. 09, 2014
Date of record				May 20, 2015
Effective date of spinoff				Jun. 01, 2015
Certain details of spinoff transaction							In June 2014, PPL and PPL Energy Supply executed definitive agreements with affiliates of Riverstone to spin off PPL Energy Supply and immediately combine it with Riverstone's competitive power generation businesses to form a new, stand-alone, publicly traded company named Talen Energy. The transaction was subject to customary closing conditions, including receipt of regulatory approvals from the NRC, FERC, DOJ and PUC, all of which were received by mid-April 2015. On April 29, 2015, PPL's Board of Directors declared the June 1, 2015 distribution to PPL's shareowners of record on May 20, 2015 of a newly formed entity, Holdco, which at closing owned all of the membership interests of PPL Energy Supply and all of the common stock of Talen Energy.
Number of shares of Talen common stock for one share of PPL common stock | shares	0.1249
Initial percent ownership in new company, Talen Energy, by PPL shareowners	65.00%
Initial percent ownership in new company, Talen Energy, by Riverstone Holdings, LLC	35.00%
Number of approaches | Integer				3
Net assets distributed	$ 3,200
Number of market approaches | Integer				2
Review period used in determining the control premium (in years)				5 years
Minimum transaction value reviewed in determining the control premium				$ 1,000
Carrying value of the Supply segment	4,100
Gain (loss) on interest rate swaps recognized in discontinued operations on the statement of income	(72)
Gain (loss), after-tax, on interest rate swaps recognized in discontinued operations on the statement of income	(42)
Adjustment for loss on spinoff	879
Continuing Involvement (Details) [Abstract]
Amount for services billed to spinoff							$ 1	35	25
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Results of Discontinued Operations (Details) [Abstract]
Operating revenues									1,427
Operating expenses									1,328
Other Income (Expense) - net									(21)
Interest expense									150
Income tax expense (benefit)									(30)
Gain (loss) on disposal group									(879)
Loss from Discontinued Operations (net of income taxes)									(921)
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Net assets distributed	3,200
PPL Energy Supply Spinoff [Member] | Talen Energy Market Value [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting				50.00%
Net assets distributed	1,400
Midpoint of premiums received in market sales transactions reviewed				25.00%
Control Premium				25.00%
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Net assets distributed	1,400
PPL Energy Supply Spinoff [Member] | Talen Energy Market Value [Member] | Minimum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control Premium				5.00%
PPL Energy Supply Spinoff [Member] | Talen Energy Market Value [Member] | Maximum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control Premium				42.00%
PPL Energy Supply Spinoff [Member] | Income Discounted Cash Flow [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting				30.00%
Net assets distributed	1,100
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Net assets distributed	1,100
PPL Energy Supply Spinoff [Member] | Alternative Market Comparable Company [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting				20.00%
Net assets distributed	$ 700
Midpoint of premiums received in market sales transactions reviewed	25.00%
Control Premium	25.00%
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Net assets distributed	$ 700
PPL Energy Supply Spinoff [Member] | Alternative Market Comparable Company [Member] | Minimum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control Premium	5.00%
PPL Energy Supply Spinoff [Member] | Alternative Market Comparable Company [Member] | Maximum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control Premium	42.00%
Spinoff [Member] | PPL Energy Supply Spinoff [Member]
Divestitures - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Separation benefits								10
Third-party costs								45
Spinoff [Member] | PPL Energy Supply Spinoff [Member] | Other Operation Maintenance [Member]
Divestitures - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Separation benefits								8
Consulting and other costs								13
Spinoff [Member] | PPL Energy Supply Spinoff [Member] | Discontinued Operations [Member]
Divestitures - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Separation benefits								2
Employee-related costs recognized	$ 24
Bank advisory, legal and accounting fees								32
PPL Electric [Member] | Northeast Pocono Reliability Project [Member]
Development Projects [Abstract]
Total length (in miles) of the expansion project | mi							58
Capacity (in kilovolts) of a transmission line | kV							230
Number of new substations included in request | Integer							3
Adder to the return on equity incentive denied in ratemaking request (in basis points) | Integer							100
Project costs capitalized							$ 350
PPL Electric [Member] | PPL Energy Supply Spinoff [Member] | Talen Energy Marketing [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases						$ 27	$ 0	106
LGE [Member]
Development Projects [Abstract]
Generating units retired at the Cane Run plant | coal-fired_unit				2	1
Costs associated with the retirement of generating units			$ 11
KU [Member]
Development Projects [Abstract]
Generating Units Retired Plant Anticipated | coal-fired_unit							2
Generating Units Retired Megawatts Anticipated | Integer							272
Generating Units Retired Plant Two | coal-fired_unit			2
Costs associated with the retirement of generating units			$ 6
LGE and KU [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Completed Megawatt Expansion Of Capacity | MW		10
Actual Capital Cost Of Expansion Project		$ 25
PPL Electric Utilities Corp [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases							$ 507	535	657
PPL Electric Utilities Corp [Member] | Northeast Pocono Reliability Project [Member]
Development Projects [Abstract]
Total length (in miles) of the expansion project | mi							58
Capacity (in kilovolts) of a transmission line | kV							230
Number of new substations included in request | Integer							3
Adder to the return on equity incentive denied in ratemaking request (in basis points) | Integer							100
Project costs capitalized							$ 350
PPL Electric Utilities Corp [Member] | PPL Energy Supply Spinoff [Member] | Talen Energy Marketing [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases						$ 27	106
LG And E And KU Energy LLC [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases							$ 178	171	184
LG And E And KU Energy LLC [Member] | LGE [Member]
Development Projects [Abstract]
Generating units retired at the Cane Run plant | coal-fired_unit				2	1
Costs associated with the retirement of generating units			$ 11
LG And E And KU Energy LLC [Member] | KU [Member]
Development Projects [Abstract]
Generating Units Retired Plant Anticipated | coal-fired_unit							2
Generating Units Retired Megawatts Anticipated | Integer							272
Generating Units Retired Plant Two | coal-fired_unit			2
Costs associated with the retirement of generating units			$ 6
LG And E And KU Energy LLC [Member] | LGE and KU [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Completed Megawatt Expansion Of Capacity | MW		10
Actual Capital Cost Of Expansion Project		$ 25
Louisville Gas And Electric Co [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases							$ 160	153	166
Development Projects [Abstract]
Generating units retired at the Cane Run plant | coal-fired_unit				2	1
Costs associated with the retirement of generating units			$ 11
Louisville Gas And Electric Co [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Completed Megawatt Expansion Of Capacity | MW		10
Actual Capital Cost Of Expansion Project		$ 25
Kentucky Utilities Co [Member]
Continuing Involvement (Details) [Abstract]
Energy purchases							$ 18	$ 18	$ 18
Development Projects [Abstract]
Generating Units Retired Plant Anticipated | coal-fired_unit							2
Generating Units Retired Megawatts Anticipated | Integer							272
Generating Units Retired Plant Two | coal-fired_unit			2
Costs associated with the retirement of generating units			$ 6
Kentucky Utilities Co [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Completed Megawatt Expansion Of Capacity | MW		10
Actual Capital Cost Of Expansion Project		$ 25