Financing Activities (Long-term Debt and Equity Securities) (Details) Share data in Millions, except Per Share data, unless otherwise specified			1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended			12 Months Ended	1 Months Ended	12 Months Ended		12 Months Ended					1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended			12 Months Ended		12 Months Ended		1 Months Ended			12 Months Ended		12 Months Ended		1 Months Ended				12 Months Ended				12 Months Ended				12 Months Ended									12 Months Ended					12 Months Ended						12 Months Ended				1 Months Ended	12 Months Ended				12 Months Ended							12 Months Ended						12 Months Ended	1 Months Ended	12 Months Ended					12 Months Ended		12 Months Ended					12 Months Ended							12 Months Ended							12 Months Ended			12 Months Ended							12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	May 31, 2014 Purchase Contacts 2011 [Member] USD ($)	Dec. 31, 2014 Purchase Contacts 2011 [Member]	Jul. 31, 2013 Purchase Contacts 2010 [Member] USD ($)	Dec. 31, 2014 Purchase Contacts 2010 [Member]	Aug. 31, 2014 PPL Energy Supply [Member] Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2014 PPL Energy Supply [Member] Senior Unsecured Notes [Member] REset Put Securities [Member] USD ($)	Dec. 31, 2014 PPL Electric [Member] Senior Secured Notes - First Mortgage Bonds [Member] 2001 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 PPL Electric [Member] Senior Secured Notes - First Mortgage Bonds [Member] 2001 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 PPL Electric [Member] Senior Secured Notes - First Mortgage Bonds [Member] Pollution Control Revenue Refunding Bonds [Member] USD ($)	Jun. 30, 2014 PPL Electric [Member] First Mortgage Bonds [Member] USD ($)	Dec. 31, 2014 PPL Electric [Member] First Mortgage Bonds [Member]	Dec. 31, 2014 LKE [Member] First Mortgage Bonds [Member] Tax Exempt Revenue Bonds [Member] USD ($)	Dec. 31, 2014 LKE [Member] First Mortgage Bonds [Member] Insured Auction Rate Securities [Member] USD ($)	Dec. 31, 2014 LGE [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 LGE [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 KU [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 KU [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Remarketed [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Remarketed [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Remarketed [Member] Junior Subordinated Notes [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Remarketed [Member] Junior Subordinated Notes [Member] Equity Units 2011 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member] Integer	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2010 [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2011 [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Senior Unsecured Notes [Member] Equity Units 2011 [Member] USD ($)	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member] USD ($)	Dec. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member]	May 31, 2013 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2010 [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2011 [Member] USD ($)	Mar. 31, 2014 PPL Capital Funding [Member] Exchanged [Member] Junior Subordinated Notes [Member] Equity Units 2011 [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] USD ($)	Dec. 31, 2013 United States of America, Dollars [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2013 United States of America, Dollars [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2014 United States of America, Dollars [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2013 United States of America, Dollars [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2014 United States of America, Dollars [Member] Junior Subordinated Notes [Member] USD ($)	Dec. 31, 2013 United States of America, Dollars [Member] Junior Subordinated Notes [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] Other [Member] USD ($)	Dec. 31, 2013 United States of America, Dollars [Member] Other [Member] USD ($)	Dec. 31, 2014 United Kingdom, Pounds [Member] USD ($)		Dec. 31, 2014 United Kingdom, Pounds [Member] GBP (£)	Dec. 31, 2013 United Kingdom, Pounds [Member] USD ($)		Dec. 31, 2014 United Kingdom, Pounds [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2014 United Kingdom, Pounds [Member] Senior Unsecured Notes [Member] GBP (£)	Dec. 31, 2013 United Kingdom, Pounds [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2014 United Kingdom, Pounds [Member] Index Linked Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2013 United Kingdom, Pounds [Member] Index Linked Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2014 United Kingdom, Pounds [Member] WPD South West And WPD East Midlands [Member] Index Linked Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD South West And WPD East Midlands [Member] Index Linked Senior Unsecured Notes [Member] GBP (£)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD South West [Member] Index Linked Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD South West [Member] Index Linked Senior Unsecured Notes [Member] GBP (£)	Dec. 31, 2014 PPL Energy Supply LLC [Member] USD ($)	Dec. 31, 2013 PPL Energy Supply LLC [Member] USD ($)	Aug. 31, 2014 PPL Energy Supply LLC [Member] Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2014 PPL Energy Supply LLC [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2013 PPL Energy Supply LLC [Member] Senior Unsecured Notes [Member] USD ($)		Dec. 31, 2014 PPL Energy Supply LLC [Member] Senior Unsecured Notes [Member] REset Put Securities [Member] USD ($)	Dec. 31, 2014 PPL Energy Supply LLC [Member] Senior Secured Notes [Member] USD ($)	Dec. 31, 2013 PPL Energy Supply LLC [Member] Senior Secured Notes [Member] USD ($)	Dec. 31, 2014 PPL Energy Supply LLC [Member] Other [Member] USD ($)	Dec. 31, 2013 PPL Energy Supply LLC [Member] Other [Member] USD ($)	Dec. 31, 2014 PPL Electric Utilities Corp [Member] USD ($)	Dec. 31, 2013 PPL Electric Utilities Corp [Member] USD ($)	Dec. 31, 2014 PPL Electric Utilities Corp [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2013 PPL Electric Utilities Corp [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2014 PPL Electric Utilities Corp [Member] Senior Secured Notes - First Mortgage Bonds [Member] 2001 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 PPL Electric Utilities Corp [Member] Senior Secured Notes - First Mortgage Bonds [Member] 2001 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 PPL Electric Utilities Corp [Member] Senior Secured Notes - First Mortgage Bonds [Member] Pollution Control Revenue Refunding Bonds [Member] USD ($)	Jun. 30, 2014 PPL Electric Utilities Corp [Member] First Mortgage Bonds [Member] USD ($)	Dec. 31, 2014 PPL Electric Utilities Corp [Member] First Mortgage Bonds [Member]	Dec. 31, 2014 PPL Electric Utilities Corp [Member] Other [Member] USD ($)	Dec. 31, 2013 PPL Electric Utilities Corp [Member] Other [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] USD ($)	Dec. 31, 2013 LG And E And KU Energy LLC [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2013 LG And E And KU Energy LLC [Member] Senior Unsecured Notes [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2013 LG And E And KU Energy LLC [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2014 LG And E And KU Energy LLC [Member] First Mortgage Bonds [Member] Tax Exempt Revenue Bonds [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] First Mortgage Bonds [Member] Insured Auction Rate Securities [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] LGE [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 LG And E And KU Energy LLC [Member] LGE [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] KU [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 LG And E And KU Energy LLC [Member] KU [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] USD ($)	Dec. 31, 2013 Louisville Gas And Electric Co [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2013 Louisville Gas And Electric Co [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2014 Louisville Gas And Electric Co [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 Louisville Gas And Electric Co [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] First Mortgage Bonds [Member] Tax Exempt Revenue Bonds [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] First Mortgage Bonds [Member] Insured Auction Rate Securities [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] USD ($)	Dec. 31, 2013 Kentucky Utilities Co [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2013 Kentucky Utilities Co [Member] Senior Secured Notes - First Mortgage Bonds [Member] USD ($)		Dec. 31, 2014 Kentucky Utilities Co [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2013 Kentucky Utilities Co [Member] First Mortgage Bonds [Member] 2010 Mortgage Indenture [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] First Mortgage Bonds [Member] Tax Exempt Revenue Bonds [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] First Mortgage Bonds [Member] Insured Auction Rate Securities [Member] USD ($)
Debt Instrument [Line Items]
Weighted-Average Rate																																											4.28%				3.83%				6.31%									5.53%		5.53%			1.83%											5.31%					8.86%						4.57%													3.31%		3.21%												2.85%										3.44%
Maturity date of long-term debt range start																																											Nov. 15, 2015				Nov. 01, 2015				Mar. 30, 2067									May 01, 2016		May 01, 2016			Jun. 01, 2043											Sep. 01, 2015											Dec. 15, 2015													Nov. 15, 2015		Nov. 01, 2015												Nov. 15, 2015										Nov. 01, 2015
Maturity date of long-term date range end																																											Mar. 15, 2044				Jun. 15, 2044				Apr. 30, 2073									Dec. 10, 2040		Dec. 10, 2040			Dec. 01, 2056											Dec. 15, 2036											Jun. 15, 2044													Oct. 01, 2021		Nov. 15, 2043												Nov. 15, 2043										Nov. 15, 2043
Principal outstanding	$ 20,426,000,000	$ 20,935,000,000						$ 300,000,000							$ 231,000,000																										$ 13,067,000,000	$ 13,314,000,000	$ 6,018,000,000	[1]	$ 5,568,000,000	[1]	$ 6,119,000,000	[2],[3],[4]	$ 5,823,000,000	[2],[3],[4]	$ 930,000,000	$ 1,908,000,000	$ 0	$ 15,000,000	$ 7,359,000,000	[5]		$ 7,621,000,000	[5]	$ 6,627,000,000	[6]		$ 6,872,000,000	[6]	$ 732,000,000	[7]	$ 749,000,000	[7]					$ 2,238,000,000	$ 2,547,000,000		$ 2,193,000,000	[1]	$ 2,493,000,000	[1]	$ 300,000,000	$ 45,000,000	$ 49,000,000	$ 0	$ 5,000,000	$ 2,614,000,000	$ 2,324,000,000	$ 2,614,000,000	[2],[3]	$ 2,314,000,000	[2],[3]						$ 0	$ 10,000,000	$ 4,585,000,000	$ 4,585,000,000	$ 1,125,000,000	$ 1,125,000,000	$ 3,460,000,000	[2],[4]	$ 3,460,000,000	[2],[4]		$ 231,000,000					$ 1,359,000,000	$ 1,359,000,000	$ 1,359,000,000	[2],[4]	$ 1,359,000,000	[2],[4]				$ 135,000,000	$ 2,101,000,000	$ 2,101,000,000	$ 2,101,000,000	[2],[4]	$ 2,101,000,000	[2],[4]				$ 96,000,000
Fair market value adjustments	18,000,000	23,000,000																																																																							(19,000,000)	(22,000,000)																								(1,000,000)	(1,000,000)													(1,000,000)	(1,000,000)									0	1,000,000
Unamortized premium and (discount), net	(53,000,000)	(51,000,000)
Unamortized discount																																																																									(1,000,000)	0											(12,000,000)	(9,000,000)												(17,000,000)	(19,000,000)													(5,000,000)	(5,000,000)									(10,000,000)	(11,000,000)
Total Long-term Debt	20,391,000,000	20,907,000,000																																																																							2,218,000,000	2,525,000,000											2,602,000,000	2,315,000,000												4,567,000,000	4,565,000,000													1,353,000,000	1,353,000,000									2,091,000,000	2,091,000,000
Less current portion of Long-term debt	1,535,000,000	315,000,000																																																																							535,000,000	304,000,000											100,000,000	10,000,000												900,000,000	0													250,000,000	0									250,000,000	0
Long-term Debt	18,856,000,000	20,592,000,000																																																																							1,683,000,000	2,221,000,000											2,502,000,000	2,305,000,000												3,667,000,000	4,565,000,000													1,103,000,000	1,353,000,000									1,841,000,000	2,091,000,000
Long-term Debt (Numeric) [Abstract]
Principal amount												300,000,000										1,150,000,000		978,000,000			250,000,000		600,000,000		300,000,000	350,000,000	400,000,000			300,000,000		850,000,000	350,000,000	400,000,000																																																						300,000,000
Stated interest rate							5.40%	5.70%				4.125%										4.625%		4.32%			1.90%		3.40%		4.70%	3.95%	5.00%			2.04%		2.77%	2.189%	3.184%																																			5.40%					5.70%														4.125%
Maturity date (in years)								Dec. 31, 2035					Jun. 15, 2044								Jul. 01, 2018			May 01, 2019		Jun. 01, 2018		Jun. 01, 2023		Jun. 01, 2043		Mar. 15, 2024	Mar. 15, 2044		Jun. 01, 2016		Jun. 01, 2018		Mar. 15, 2017	Mar. 15, 2019																																								Dec. 31, 2035	Nov. 30, 2025														Jun. 15, 2044
Percentage of principal amount the remarketing dealer will pay if the REPS are purchased for remarketing								100.00%																																																																								100.00%
Aggregate carrying value of property subject to lien									5,800,000,000	5,100,000,000						3,700,000,000	3,200,000,000	5,500,000,000	5,100,000,000																																																																								5,800,000,000	5,100,000,000																3,700,000,000	3,200,000,000	5,500,000,000	5,100,000,000							3,700,000,000	3,200,000,000									5,500,000,000	5,100,000,000
Principal amount that may be redeemed at a future date											224,000,000																																																																																		224,000,000
Earliest date the company may redeem the debt											Feb. 15, 2015																																																																																		Feb. 15, 2015
Principal amount that may be redeemed in whole or in part											90,000,000																																																																																		90,000,000
Earliest date the company may redeem the debt in whole or in part											Oct. 01, 2020																																																																																		Oct. 01, 2020
Aggregate amount of tax-exempt revenue bonds in a term rate mode														418,000,000																																																																																												418,000,000														391,000,000										27,000,000
Aggregate amount of tax-exempt revenue bonds in a variable rate mode														507,000,000																																																																																												507,000,000														183,000,000										324,000,000
Maximum number of days wherein interest rates reset															weekly or every 35 days																																																																																												weekly or every 35 days														weekly or every 35 days										weekly or every 35 days
Principal amount that may be redeemed in total but not in part																																																												352,000,000		225,000,000
Earliest date the company may redeem the debt in total but not in part																																																												Dec. 21, 2026		Dec. 21, 2026
Principal amount that may be redeemed in total by series																																																																							352,000,000	225,000,000
Earliest date the company may redeem the debt in total by series																																																																							Dec. 01, 2026	Dec. 01, 2026
Increase (decrease) in principal due to inflation																																																																					16,000,000	10,000,000
Principal amount that may be put back to the issuer														251,000,000																																									5,900,000,000		3,800,000,000																																																	251,000,000														23,000,000										228,000,000
Number of tranches of debt entered into relating to the debt extinguishment																									3
Portion of total principal settled in cash																							228,000,000
Gain (loss) on extinguishment of debt																				(9,000,000)														(10,000,000)
Net proceeds from issuance of unsecured debt												294,000,000																																																																																		294,000,000
Repayments of senior notes							300,000,000																																																																				300,000,000
Aggregate maturities of long-term debt (Details) [Abstract]
2015	1,535,000,000																																																																								535,000,000												100,000,000													900,000,000														250,000,000										250,000,000
2016	839,000,000																																																																								354,000,000												0													25,000,000														25,000,000										0
2017	298,000,000																																																																								4,000,000												0													194,000,000														194,000,000										0
2018	750,000,000																																																																								403,000,000												0													98,000,000														98,000,000										0
2019	44,000,000																																																																								4,000,000												0													40,000,000														40,000,000										0
Thereafter	16,960,000,000																																																																								938,000,000												2,514,000,000													3,328,000,000														752,000,000										1,851,000,000
Equity Securities (Numeric) [Abstract]
Stock issuance date				May 31, 2014		Jul. 31, 2013
Shares of PPL common stock issued			31.7		40.0
Price per share of PPL common stock issued			$ 30.86		$ 28.73
Net cash received on stock transaction			$ 978,000,000		$ 1,150,000,000

[1] Includes $300million of 5.70%REset Put Securities due 2035 (REPS). The REPS bear interest at a rate of 5.70% per annum to, but excluding, October 15, 2015 (Remarketing Date). The REPS are required to be put by existing holders on the Remarketing Date either for (a) purchase and remarketing by a designated remarketing dealer or (b) repurchase by PPL Energy Supply. If the remarketing dealer elects to purchase the REPS for remarketing, it will purchase the REPS at 100% of the principal amount, and the REPS will bear interest on and after the Remarketing Date at a new fixed rate per annum determined in the remarketing. PPL Energy Supply has the right to terminate the remarketing process. If the remarketing is terminated at the option of PPL Energy Supply or under certain other circumstances, including the occurrence of an event of default by PPLEnergy Supply under the related indenture or a failed remarketing for certain specified reasons, PPL Energy Supply will be required to pay the remarketing dealer a settlement amount as calculated in accordance with the related remarketing agreement.

[2] IncludesPPL Electric's senior secured and first mortgage bonds that are secured by the lien of PPL Electric's 2001 Mortgage Indenture, which covers substantially all electric distribution plant and certain transmission plant owned by PPL Electric. The carrying value of PPL Electric's property, plant and equipment was approximately $5.8 billion and $5.1 billion at December 31, 2014 and 2013. Includes LG&E's first mortgage bonds that are secured by the lien of the LG&E 2010 Mortgage Indenture which creates a lien, subject to certain exceptions and exclusions, on substantially all of LG&E's real and tangible personal property located in Kentucky and used or to be used in connection with the generation, transmission and distribution of electricity and the storage and distribution of natural gas. The aggregate carrying value of the property subject to the lien was $3.7 billion and $3.2 billion at December 31, 2014 and 2013. Includes KU's first mortgage bonds that are secured by the lien of the KU 2010 Mortgage Indenture which creates a lien, subject to certain exceptions and exclusions, on substantially all of KU's real and tangible personal property located in Kentucky and used or to be used in connection with the generation, transmission and distribution of electricity. The aggregate carrying value of the property subject to the lien was $5.5 billion and $5.1 billion at December 31, 2014 and 2013.

[3] Includes PPL Electric'sseries of senior secured bonds that secure its obligations to make payments with respect to each series of Pollution Control Bonds that were issued by the LCIDA and the PEDFA on behalf of PPL Electric. These senior secured bonds were issued in the same principal amount, contain payment and redemption provisions that correspond to and bear the same interest rate as such Pollution Control Bonds. These senior secured bonds were issued under PPL Electric's 2001 Mortgage Indenture and are secured as noted in (b) above. This amount includes $224 million that may be redeemed at par beginning in 2015 and $90 million that may be redeemed, in whole or in part, at par beginning in October 2020 and are subject to mandatory redemption upon determination that the interest rate on the bonds would be included in the holders' gross income for federal tax purposes.

[4] Includes LG&E's and KU's series of first mortgage bonds that were issued to the respective trustees of tax-exempt revenue bonds to secure its respective obligations to make payments with respect to each series of bonds. The first mortgage bonds were issued in the same principal amounts, contain payment and redemption provisions that correspond to and bear the same interest rate as such tax-exempt revenue bonds. These first mortgage bonds were issued under the LG&E 2010 Mortgage Indenture and the KU 2010 Mortgage Indenture and are secured as noted in (b) above. The related tax-exempt revenue bonds were issued by various governmental entities, principally counties in Kentucky, on behalf of LG&E and KU. The related revenue bond documents allow LG&E and KU to convert the interest rate mode on the bonds from time to time to a commercial paper rate, daily rate, weekly rate, term rate of at least one year or, in some cases, an auction rate or a LIBOR index rate. At December 31, 2014, the aggregate tax-exempt revenue bonds issued on behalf of LG&E and KU that were in a term rate mode totaled $418 million for LKE, comprised of $391 million and $27 million for LG&E and KU, respectively. At December 31, 2014, the aggregate tax-exempt revenue bonds issued on behalf of LG&E and KU that were in a variable rate mode totaled $507 million for LKE, comprised of $183 million and $324 million for LG&E and KU, respectively. Several series of the tax-exempt revenue bonds are insured by monoline bond insurers whose ratings were reduced due to exposures relating to insurance of sub-prime mortgages. Of the bonds outstanding, $231 million are in the form of insured auction rate securities ($135 million for LG&E and $96 million for KU), wherein interest rates are reset either weekly or every 35 days via an auction process. Beginning in late 2007, the interest rates on these insured bonds began to increase due to investor concerns about the creditworthiness of the bond insurers. During 2008, interest rates increased, and LG&E and KU experienced failed auctions when there were insufficient bids for the bonds. When a failed auction occurs, the interest rate is set pursuant to a formula stipulated in the indenture. As noted above, the instruments governing these auction rate bonds permit LG&E and KU to convert the bonds to other interest rate modes. Certain variable rate tax-exempt revenue bonds totaling $251 million at December 31, 2014 ($23 million for LG&E and $228 million for KU), are subject to tender for purchase by LG&E and KU at the option of the holder and to mandatory tender for purchase by LG&E and KU upon the occurrence of certain events.

[5] Includes £3.8 billion ($5.9 billion at December 31, 2014) of notes that may be put by the holders to the issuer for redemption if the long-term credit ratings assigned to the notes are withdrawn by any of the rating agencies (Moody's, S&P or Fitch) or reduced to a non-investment grade rating of Ba1 or BB+ in connection with a restructuring event which includes the loss of, or a material adverse change to, the distribution licenses under which the issuer operates.

[6] Includes £225 million ($352 million at December 31, 2014) of notes that may be redeemed, in total but not in part, on December 21, 2026, at the greater of the principal value or a value determined by reference to the gross redemption yield on a nominated U.K. Government bond.

[7] The principal amount of the notes issued by WPD (South West) and WPD (East Midlands) is adjusted based on changes in a specified index, as detailed in the terms of the related indentures. The adjustment to the principal amounts from 2013 to 2014 was an increase of approximately £10million ($16million) resulting from inflation. In addition, this amount includes £225 million ($352 million at December 31, 2014)of notes issued by WPD (South West)that may be redeemed, in total by series, on December 1, 2026, at the greater of the adjusted principal value and a make-whole value determined by reference to the gross real yield on a nominated U.K. government bond.