Utility Rate Regulation (Regulatory Matters) (Details) $ in Millions				1 Months Ended		12 Months Ended
	Nov. 23, 2016 USD ($)	Aug. 08, 2016	Sep. 03, 2015 USD ($)	Aug. 31, 2016	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) Integer	Dec. 31, 2014 USD ($)
Regulatory Matters - United Kingdom Activities - Ofgem Review of Line Loss Calculation (Numeric) [Abstract]
Number Of Distribution Network Operators | Integer							4
Charge to income during period for line loss incentive/penalty liability						$ 0	$ 0	$ 65
Liability at period end regarding line loss incentive/penalty						$ 26	$ 61
Minimum [Member]
Regulatory Matters - United Kingdom Activities - Ofgem Review of Line Loss Calculation (Numeric) [Abstract]
Customer liability refund date						Apr. 01, 2015
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						10 years
Maximum [Member]
Regulatory Matters - United Kingdom Activities - Ofgem Review of Line Loss Calculation (Numeric) [Abstract]
Customer liability refund date						Mar. 31, 2019
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						25 years
Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]
Regulatory Matters - Kentucky Activities - CPCN and ECR Filings (Numeric) [Abstract]
Return on equity		9.80%
PPL Electric [Member]
Regulatory Matters - Pennsylvania Activities - Act 129 (Numeric) [Abstract]
Minimum term of long term supply contract under Act 129 (in years)						4 years
Maximum term of long term supply contract under Act 129 (in years)						20 years
Maximum percentage of long-term contracts that can be included in the mix of PLR supply contracts under Act 129						25.00%
Maximum amount of costs that can be recovered under the Act 129 Phase III plan						$ 313
Period over which program costs can be recovered (in years)						5 years
PPL Electric [Member] | Distribution Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing					$ 168
Increase in annual revenue requirements associated with base rates resulting from rate case			$ 124
LKE [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Kentucky Activities - CPCN and ECR Filings (Numeric) [Abstract]
Return on equity						9.80%
Regulatory Matters - Federal Matters - Federal Energy Regulatory Commission Wholesale Formula Rates (Numeric) [Abstract]
Construction Projects Begin Date		Dec. 31, 2016
Construction Project Expected End Date		Dec. 31, 2023
LGE [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Requested return on equity	10.23%
LGE [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 94
Percentage requested increase in base rates with anticipated rate case filing	8.50%
LGE [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 14
Percentage requested increase in base rates with anticipated rate case filing	4.20%
KU [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Requested return on equity	10.23%
KU [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 103
Percentage requested increase in base rates with anticipated rate case filing	6.40%
PPL Electric Utilities Corp [Member] | Distribution Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Increase in annual revenue requirements associated with base rates resulting from rate case			$ 124
PPL Electric Utilities Corp [Member]
Regulatory Matters - Pennsylvania Activities - Act 129 (Numeric) [Abstract]
Minimum term of long term supply contract under Act 129 (in years)						4 years
Maximum term of long term supply contract under Act 129 (in years)						20 years
Maximum percentage of long-term contracts that can be included in the mix of PLR supply contracts under Act 129						25.00%
Maximum amount of costs that can be recovered under the Act 129 Phase III plan						$ 313
Period over which program costs can be recovered (in years)						5 years
PPL Electric Utilities Corp [Member] | Distribution Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing					$ 168
LG And E And KU Energy LLC [Member]
Regulatory Matters - Kentucky Activities - Gas Franchise (Numeric) [Abstract]
Franchise Agreement Term				5 years
Days of Notice to Modify Franchise Fee				60 days
Franchise Fee Cap				3.00%
Franchise Fee If Recovered From Customers				0.00%
LG And E And KU Energy LLC [Member] | Minimum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						10 years
LG And E And KU Energy LLC [Member] | Maximum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						25 years
LG And E And KU Energy LLC [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Requested return on equity	10.23%
Regulatory Matters - Federal Matters - Federal Energy Regulatory Commission Wholesale Formula Rates (Numeric) [Abstract]
Construction Projects Begin Date		Dec. 31, 2016
Construction Project Expected End Date		Dec. 31, 2023
LG And E And KU Energy LLC [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]
Regulatory Matters - Kentucky Activities - CPCN and ECR Filings (Numeric) [Abstract]
Return on equity		9.80%				9.80%
LG And E And KU Energy LLC [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 14
Percentage requested increase in base rates with anticipated rate case filing	4.20%
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 94
Percentage requested increase in base rates with anticipated rate case filing	8.50%
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 103
Percentage requested increase in base rates with anticipated rate case filing	6.40%
Louisville Gas And Electric Co [Member]
Regulatory Matters - Kentucky Activities - Gas Franchise (Numeric) [Abstract]
Franchise Agreement Term				5 years
Days of Notice to Modify Franchise Fee				60 days
Franchise Fee Cap				3.00%
Louisville Gas And Electric Co [Member] | Minimum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						10 years
Louisville Gas And Electric Co [Member] | Maximum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						25 years
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Requested return on equity	10.23%
Regulatory Matters - Federal Matters - Federal Energy Regulatory Commission Wholesale Formula Rates (Numeric) [Abstract]
Construction Projects Begin Date		Dec. 31, 2016
Construction Project Expected End Date		Dec. 31, 2023
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]
Regulatory Matters - Kentucky Activities - CPCN and ECR Filings (Numeric) [Abstract]
Return on equity		9.80%				9.80%
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 94
Percentage requested increase in base rates with anticipated rate case filing	8.50%
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 14
Percentage requested increase in base rates with anticipated rate case filing	4.20%
Kentucky Utilities Co [Member] | Minimum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						10 years
Kentucky Utilities Co [Member] | Maximum [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Amortization period for the deferred recovery of a regulatory asset						25 years
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Requested return on equity	10.23%
Regulatory Matters - Federal Matters - Federal Energy Regulatory Commission Wholesale Formula Rates (Numeric) [Abstract]
Construction Projects Begin Date		Dec. 31, 2016
Construction Project Expected End Date		Dec. 31, 2023
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]
Regulatory Matters - Kentucky Activities - CPCN and ECR Filings (Numeric) [Abstract]
Return on equity		9.80%				9.80%
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Rate Case Proceedings / Federal Energy Regulatory Commission Formula Rates (Numeric) [Abstract]
Dollar amount requested increase in base rates with anticipated rate case filing	$ 103
Percentage requested increase in base rates with anticipated rate case filing	6.40%