Financing Activities - Credit Arrangements (Details) £ in Millions, $ in Millions		1 Months Ended	6 Months Ended
		Jul. 31, 2016	Jun. 30, 2016 USD ($)	Jun. 30, 2016 GBP (£)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 GBP (£)
WPD PLC [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jan. 13, 2021
Interest rate on outstanding borrowing			1.27%	1.27%	1.83%	1.83%
WPD South West [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jul. 01, 2020
Interest rate on outstanding borrowing			0.92%	0.92%
WPD South West [Member] | Syndicated Credit Facility [Member] | Subsequent Event [Member]
Line of Credit Facility [Line Items]
Expiration date		Jul. 29, 2021
WPD East Midlands [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jul. 01, 2020
Interest rate on outstanding borrowing			0.92%	0.92%
WPD East Midlands [Member] | Syndicated Credit Facility [Member] | Subsequent Event [Member]
Line of Credit Facility [Line Items]
Expiration date		Jul. 29, 2021
WPD West Midlands [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jul. 01, 2020
WPD West Midlands [Member] | Syndicated Credit Facility [Member] | Subsequent Event [Member]
Line of Credit Facility [Line Items]
Expiration date		Jul. 29, 2021
WPD [Member]
Line of Credit Facility [Line Items]
Unused capacity			$ 1,200
PPL Capital Funding [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jan. 29, 2021
PPL Capital Funding [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Nov. 12, 2018
PPL Capital Funding [Member] | Bilateral Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Mar. 17, 2017
PPL Electric [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jan. 29, 2021
LKE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Oct. 31, 2018
Interest rate on outstanding borrowing					1.68%	1.68%
LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Oct. 01, 2017
United Kingdom, Pounds [Member]
Line of Credit Facility [Line Items]
Capacity | £	[1]			£ 1,095
Borrowed | £	[1]			269		£ 133
Letters of credit and commercial paper issued | £	[1]			4		4
Unused capacity | £	[1]			822
United Kingdom, Pounds [Member] | WPD PLC [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity | £				210
Borrowed			$ 200	138		133
Unused capacity | £				72
United Kingdom, Pounds [Member] | WPD South West [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity | £				245
Borrowed			146	100
Unused capacity | £				145
United Kingdom, Pounds [Member] | WPD East Midlands [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity | £				300
Borrowed			45	31
Unused capacity | £				269
United Kingdom, Pounds [Member] | WPD West Midlands [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity | £				300
Unused capacity | £				300
United Kingdom, Pounds [Member] | WPD [Member] | Uncommitted Credit Facilities [Member]
Line of Credit Facility [Line Items]
Capacity | £				40
Letters of credit and commercial paper issued | £				4		£ 4
Unused capacity | £				£ 36
United States of America, Dollars [Member] | PPL Capital Funding [Member]
Line of Credit Facility [Line Items]
Capacity			1,150
Letters of credit and commercial paper issued			337		$ 471
Unused capacity			813
United States of America, Dollars [Member] | PPL Capital Funding [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			700
Letters of credit and commercial paper issued			320		151
Unused capacity			380
United States of America, Dollars [Member] | PPL Capital Funding [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			300
Letters of credit and commercial paper issued					300
Unused capacity			300
United States of America, Dollars [Member] | PPL Capital Funding [Member] | Bilateral Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			150
Letters of credit and commercial paper issued			17		20
Unused capacity			133
United States of America, Dollars [Member] | PPL Electric [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			400
Letters of credit and commercial paper issued			7		1
Unused capacity			393
United States of America, Dollars [Member] | LKE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			75
Borrowed	[2]				75
Unused capacity			75
United States of America, Dollars [Member] | LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			500
Letters of credit and commercial paper issued			110		142
Unused capacity			390
United States of America, Dollars [Member] | KU [Member]
Line of Credit Facility [Line Items]
Capacity			598
Letters of credit and commercial paper issued			227		246
Unused capacity			371
United States of America, Dollars [Member] | KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			400
Letters of credit and commercial paper issued			29		48
Unused capacity			371
United States of America, Dollars [Member] | KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			198
Letters of credit and commercial paper issued			198		198
Unused capacity			$ 0
PPL Electric Utilities Corp [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Jan. 29, 2021
PPL Electric Utilities Corp [Member] | United States of America, Dollars [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			$ 400
Letters of credit and commercial paper issued			7		$ 1
Unused capacity			$ 393
LG And E And KU Energy LLC [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date	[2]		Oct. 31, 2018
Interest rate on outstanding borrowing					1.68%	1.68%
LG And E And KU Energy LLC [Member] | LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
LG And E And KU Energy LLC [Member] | KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
LG And E And KU Energy LLC [Member] | KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Oct. 01, 2017
LG And E And KU Energy LLC [Member] | United States of America, Dollars [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity	[2]		$ 75
Borrowed	[2]				$ 75
Unused capacity	[2]		75
LG And E And KU Energy LLC [Member] | United States of America, Dollars [Member] | LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			500
Letters of credit and commercial paper issued			110		142
Unused capacity			390
LG And E And KU Energy LLC [Member] | United States of America, Dollars [Member] | KU [Member]
Line of Credit Facility [Line Items]
Capacity			598
Letters of credit and commercial paper issued			227		246
Unused capacity			371
LG And E And KU Energy LLC [Member] | United States of America, Dollars [Member] | KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			400
Letters of credit and commercial paper issued			29		48
Unused capacity			371
LG And E And KU Energy LLC [Member] | United States of America, Dollars [Member] | KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			198
Letters of credit and commercial paper issued			198		198
Unused capacity			$ 0
Louisville Gas And Electric Co [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
Louisville Gas And Electric Co [Member] | United States of America, Dollars [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			$ 500
Letters of credit and commercial paper issued			110		142
Unused capacity			$ 390
Kentucky Utilities Co [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Dec. 31, 2020
Kentucky Utilities Co [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration date			Oct. 01, 2017
Kentucky Utilities Co [Member] | United States of America, Dollars [Member]
Line of Credit Facility [Line Items]
Capacity			$ 598
Letters of credit and commercial paper issued			227		246
Unused capacity			371
Kentucky Utilities Co [Member] | United States of America, Dollars [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			400
Letters of credit and commercial paper issued			29		48
Unused capacity			371
Kentucky Utilities Co [Member] | United States of America, Dollars [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Capacity			198
Letters of credit and commercial paper issued			198		$ 198
Unused capacity			$ 0

[1] WPD plc's amounts borrowed at June 30, 2016 and December 31, 2015 were USD-denominated borrowings of $200 million for both periods, which bore interest at 1.27% and 1.83%. The unused capacity reflects the amount borrowed in GBP of £138 million as of the date borrowed. WPD (South West) amount borrowed at June 30, 2016 was a GBP-denominated borrowing which equated to $146 million and bore interest at 0.92%. WPD (East Midlands) amount borrowed at June 30, 2016 was a GBP-denominated borrowing which equated to $45 million and bore interest at 0.92%. At June 30, 2016, the unused capacity under the U.K. credit facilities was approximately $1.2 billion.

[2] LKE's interest rate on outstanding borrowings at December 31, 2015 was 1.68%.