Financing Activities - Long-term Debt (Details) £ in Millions, $ in Millions	1 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 GBP (£)	Jun. 30, 2019 USD ($)	Apr. 30, 2019 USD ($)	Oct. 31, 2019 USD ($)	Sep. 30, 2019 GBP (£)	Sep. 17, 2019	Jun. 30, 2019 GBP (£)
WPD East Midlands [Member] | Senior Notes [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount | £						£ 250
Stated interest rate	1.75%					1.75%
Proceeds from Issuance of Secured Debt	$ 301	£ 245
WPD PLC [Member] | Term Loan Facility [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount | £								£ 50
Stated interest rate			2.189%					2.189%
Proceeds from Issuance of Secured Debt			$ 63
Debt instrument term (in years)			5 years
PPL Electric [Member] | Senior Secured Bonds 5.15% Series Due 2020 [Member] | Intent to Redeem Bond [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount					$ 100
Stated interest rate					5.15%
PPL Electric [Member] | First Mortgage [Member] | First Mortgage Bond Due 2049 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 400
Stated interest rate	3.00%					3.00%
Proceeds from Issuance of Secured Debt	$ 390
LGE [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 128
Stated interest rate				1.85%
LGE [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 31
Stated interest rate			1.65%					1.65%
LGE [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 35
Stated interest rate			1.65%					1.65%
LGE [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Stated interest rate							1.75%
LGE [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Interest Rate Conversion [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 40
LGE [Member] | First Mortgage [Member] | First Mortgage Bond Due 2049 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 400
Stated interest rate				4.25%
Proceeds from Issuance of Secured Debt				$ 396
KU [Member] | Pollution Control Revenue Refunding Bonds, 2016 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 96
Stated interest rate	1.55%					1.55%
KU [Member] | Environmental Facilities Revenue Refunding Bonds, 2006 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 54
Stated interest rate	1.20%					1.20%
KU [Member] | Environmental Facilities Revenue Bonds, 2008 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 78
Stated interest rate	1.20%					1.20%
KU [Member] | Solid Waste Disposal Facility Revenue Bonds, 2000 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 13
Stated interest rate	1.30%					1.30%
KU [Member] | Environmental Facilities Revenue Bonds, 2004 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 50
Stated interest rate	1.75%					1.75%
KU [Member] | First Mortgage [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 300
Stated interest rate				4.375%
Proceeds from Issuance of Secured Debt				$ 303
PPL Electric Utilities Corp [Member] | Senior Secured Bonds 5.15% Series Due 2020 [Member] | Intent to Redeem Bond [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount					$ 100
Stated interest rate					5.15%
PPL Electric Utilities Corp [Member] | First Mortgage [Member] | First Mortgage Bond Due 2049 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 400
Stated interest rate	3.00%					3.00%
Proceeds from Issuance of Secured Debt	$ 390
LG And E And KU Energy LLC [Member] | LGE [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 128
Stated interest rate				1.85%
LG And E And KU Energy LLC [Member] | LGE [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 31
Stated interest rate			1.65%					1.65%
LG And E And KU Energy LLC [Member] | LGE [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 35
Stated interest rate			1.65%					1.65%
LG And E And KU Energy LLC [Member] | LGE [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Stated interest rate							1.75%
LG And E And KU Energy LLC [Member] | LGE [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Interest Rate Conversion [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 40
LG And E And KU Energy LLC [Member] | LGE [Member] | First Mortgage [Member] | First Mortgage Bond Due 2049 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 400
Stated interest rate				4.25%
Proceeds from Issuance of Secured Debt				$ 396
LG And E And KU Energy LLC [Member] | KU [Member] | Pollution Control Revenue Refunding Bonds, 2016 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 96
Stated interest rate	1.55%					1.55%
LG And E And KU Energy LLC [Member] | KU [Member] | Environmental Facilities Revenue Refunding Bonds, 2006 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 54
Stated interest rate	1.20%					1.20%
LG And E And KU Energy LLC [Member] | KU [Member] | Environmental Facilities Revenue Bonds, 2008 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 78
Stated interest rate	1.20%					1.20%
LG And E And KU Energy LLC [Member] | KU [Member] | Solid Waste Disposal Facility Revenue Bonds, 2000 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 13
Stated interest rate	1.30%					1.30%
LG And E And KU Energy LLC [Member] | KU [Member] | Environmental Facilities Revenue Bonds, 2004 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 50
Stated interest rate	1.75%					1.75%
LG And E And KU Energy LLC [Member] | KU [Member] | First Mortgage [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 300
Stated interest rate				4.375%
Proceeds from Issuance of Secured Debt				$ 303
Louisville Gas And Electric Co [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 128
Stated interest rate				1.85%
Louisville Gas And Electric Co [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 31
Stated interest rate			1.65%					1.65%
Louisville Gas And Electric Co [Member] | Environmental Facilities Revenue Refunding Bonds, 2007 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 35
Stated interest rate			1.65%					1.65%
Louisville Gas And Electric Co [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Stated interest rate							1.75%
Louisville Gas And Electric Co [Member] | Louisville/Jefferson County Metro Government of Kentucky Pollution Control Revenue Bonds, 2005 Series A [Member] | Interest Rate Conversion [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 40
Louisville Gas And Electric Co [Member] | First Mortgage [Member] | First Mortgage Bond Due 2049 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 400
Stated interest rate				4.25%
Proceeds from Issuance of Secured Debt				$ 396
Kentucky Utilities Co [Member] | Pollution Control Revenue Refunding Bonds, 2016 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 96
Stated interest rate	1.55%					1.55%
Kentucky Utilities Co [Member] | Environmental Facilities Revenue Refunding Bonds, 2006 Series B [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 54
Stated interest rate	1.20%					1.20%
Kentucky Utilities Co [Member] | Environmental Facilities Revenue Bonds, 2008 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 78
Stated interest rate	1.20%					1.20%
Kentucky Utilities Co [Member] | Solid Waste Disposal Facility Revenue Bonds, 2000 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 13
Stated interest rate	1.30%					1.30%
Kentucky Utilities Co [Member] | Environmental Facilities Revenue Bonds, 2004 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 50
Stated interest rate	1.75%					1.75%
Kentucky Utilities Co [Member] | First Mortgage [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount				$ 300
Stated interest rate				4.375%
Proceeds from Issuance of Secured Debt				$ 303