Financing Activities (Credit Arrangements) (Details) In Millions, unless otherwise specified	3 Months Ended		3 Months Ended			3 Months Ended		3 Months Ended					3 Months Ended					3 Months Ended																																														3 Months Ended					3 Months Ended																3 Months Ended			3 Months Ended
	Mar. 31, 2015 WPD Limited [Member] Syndicated Credit Facility [Member]	Dec. 31, 2014 WPD Limited [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 WPD South West [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 WPD East Midlands [Member] Syndicated Credit Facility [Member]	Dec. 31, 2014 WPD East Midlands [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 WPD West Midlands [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 WPD [Member] USD ($)	Mar. 31, 2015 PPL Capital Funding [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 PPL Capital Funding [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 PPL Capital Funding [Member] Bilateral Credit Facility [Member]	Mar. 31, 2015 PPL Energy Supply [Member] Syndicated Credit Facility [Member]	Dec. 31, 2014 PPL Energy Supply [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 PPL Energy Supply [Member] Facility Agreement [Member] USD ($)	Mar. 31, 2015 PPL Energy Supply [Member] Secured Trading Facility [Member] USD ($) Integer	Mar. 31, 2015 PPL Electric [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LKE [Member] Syndicated Credit Facility [Member]	Dec. 31, 2014 LKE [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LKE [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LGE [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 KU [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 KU [Member] Letter Of Credit Facility [Member]	Mar. 31, 2015 United Kingdom, Pounds [Member] GBP (£)		Dec. 31, 2014 United Kingdom, Pounds [Member] GBP (£)		Mar. 31, 2015 United Kingdom, Pounds [Member] WPD Limited [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD Limited [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD Limited [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD Limited [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD South West [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD East Midlands [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD East Midlands [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD West Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2015 United Kingdom, Pounds [Member] WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Dec. 31, 2014 United Kingdom, Pounds [Member] WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Capital Funding [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] PPL Capital Funding [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Capital Funding [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Capital Funding [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Capital Funding [Member] Bilateral Credit Facility [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] PPL Capital Funding [Member] Bilateral Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Capital Funding [Member] Uncommitted Credit Facilities [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] PPL Capital Funding [Member] Uncommitted Credit Facilities [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2014 United States of America, Dollars [Member] PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)		Mar. 31, 2015 United States of America, Dollars [Member] PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] LKE [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2014 United States of America, Dollars [Member] LKE [Member] Syndicated Credit Facility [Member] USD ($)		Mar. 31, 2015 United States of America, Dollars [Member] LGE [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] LGE [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] KU [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] KU [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] KU [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] KU [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 United States of America, Dollars [Member] KU [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2014 United States of America, Dollars [Member] KU [Member] Letter Of Credit Facility [Member] USD ($)	Mar. 31, 2015 PPL Electric Utilities Corp [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 PPL Electric Utilities Corp [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 PPL Electric Utilities Corp [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 LG And E And KU Energy LLC [Member] Syndicated Credit Facility [Member]	Dec. 31, 2014 LG And E And KU Energy LLC [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LG And E And KU Energy LLC [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LG And E And KU Energy LLC [Member] LGE [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LG And E And KU Energy LLC [Member] KU [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 LG And E And KU Energy LLC [Member] KU [Member] Letter Of Credit Facility [Member]	Mar. 31, 2015 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2014 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)		Mar. 31, 2015 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] LGE [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] LGE [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] USD ($)	Mar. 31, 2015 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2014 LG And E And KU Energy LLC [Member] United States of America, Dollars [Member] KU [Member] Letter Of Credit Facility [Member] USD ($)	Mar. 31, 2015 Louisville Gas And Electric Co [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 Louisville Gas And Electric Co [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 Louisville Gas And Electric Co [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 Kentucky Utilities Co [Member] Syndicated Credit Facility [Member]	Mar. 31, 2015 Kentucky Utilities Co [Member] Letter Of Credit Facility [Member]	Mar. 31, 2015 Kentucky Utilities Co [Member] United States of America, Dollars [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] United States of America, Dollars [Member] USD ($)	Mar. 31, 2015 Kentucky Utilities Co [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] United States of America, Dollars [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2015 Kentucky Utilities Co [Member] United States of America, Dollars [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2014 Kentucky Utilities Co [Member] United States of America, Dollars [Member] Letter Of Credit Facility [Member] USD ($)
Financing Activities [Line Items]
Expiration date	Dec. 01, 2016		Jul. 01, 2019	Jul. 01, 2019		Jul. 01, 2019		Jul. 28, 2019	Nov. 12, 2018	Mar. 26, 2016	Nov. 06, 2017		Jun. 30, 2017	Nov. 03, 2019	Jul. 28, 2019			Oct. 31, 2018	Jul. 29, 2019	Jul. 29, 2019	Oct. 01, 2017																																											Jul. 28, 2019					Oct. 31, 2018	Jul. 29, 2019	Jul. 29, 2019	Oct. 01, 2017													Jul. 29, 2019			Jul. 29, 2019	Oct. 01, 2017
Capacity																						£ 1,120	[1]				£ 210			£ 245		£ 300			£ 300	£ 65		$ 815		$ 300	$ 300	$ 150		$ 65		$ 3,000	[2]			$ 300		$ 75	[2]			$ 500		$ 598		$ 400		$ 198			$ 300								$ 75	[2]			$ 500		$ 598		$ 400		$ 198			$ 500				$ 598		$ 400		$ 198
Borrowed																						277	[1]	167	[1]	200	130	161	103		226	147	100	64												600	[2]	630	[2]			75	[2]	75	[2]																		75	[2]	75	[2]
Letters of credit and commercial paper issued																						5	[1]	5	[1]											5	5	33	22			32	21	1	1	267	[2]	121	[2]	86	1					216	264	391	434	193	236	198	198		86	1											216	264	391	434	193	236	198	198		216	264			391	434	193	236	198	198
Unused capacity							1,300															838	[1]				80			245		153			300	60		782		300	300	118		64		2,133	[2]			214						284		207		207					214												284		207		207					284				207		207
Interest rate on outstanding borrowing	1.87%	1.86%		1.00%	1.00%						2.12%	2.05%				1.68%	1.67%																																																		1.68%	1.67%
Potential maximum Facility Agreement capacity													500
Secured energy marketing and trading facility capacity														800
Automatic renewal term (in years)														1
Secured obligations outstanding														$ 88

[1] WPD Ltd.'s amounts borrowed at March 31, 2015 and December 31, 2014 were USD-denominated borrowings of $200 million and $161 million, which bore interest at 1.87% and 1.86%. WPD (East Midlands) amounts borrowed at March 31, 2015 and December 31, 2014 were GBP-denominated borrowings which equated to $226 million and $100 million, which bore interest at 1.00% for both periods. At March 31, 2015, the unused capacity under the U.K. credit facilities was $1.3 billion.

[2] At March 31, 2015, PPL Energy Supply’s and LKE’s interest rates on outstanding borrowings were 2.12% and 1.68%. At December 31, 2014, PPL Energy Supply’s and LKE’s interest rates on outstanding borrowings were 2.05% and 1.67%.