Financing Activities (Long-term Debt and Equity Securities) (Details) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended	9 Months Ended
	Oct. 31, 2015 USD ($)	Feb. 26, 2015 USD ($) Integer	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($)
At-the-Market Stock Offering Program (Numeric) [Abstract]
Net proceeds from issuance of common stock				$ 145	$ 1,037
First Mortgage Bond [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 1,050	1,050
PPL Electric [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 350
Stated interest rate	4.15%
Maturity date	Oct. 01, 2045
Proceeds from issuance of secured debt	$ 345
LGE [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 300	$ 300
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 298
LGE [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
KU [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 248
KU [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
PPL Electric Utilities Corp [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 350
Stated interest rate	4.15%
Maturity date	Oct. 01, 2045
Proceeds from issuance of secured debt	$ 345
LG And E And KU Energy LLC [Member] | First Mortgage Bond [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 1,050	1,050
LG And E And KU Energy LLC [Member] | LGE [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 300	$ 300
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 298
LG And E And KU Energy LLC [Member] | LGE [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
LG And E And KU Energy LLC [Member] | KU [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 248
LG And E And KU Energy LLC [Member] | KU [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
Louisville Gas And Electric Co [Member] | First Mortgage Bond [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 550	550
Louisville Gas And Electric Co [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 300	$ 300
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 298
Louisville Gas And Electric Co [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
Kentucky Utilities Co [Member] | First Mortgage Bond [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 500	500
Kentucky Utilities Co [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2025 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			3.30%	3.30%
Maturity date				Oct. 01, 2025
Proceeds from issuance of secured debt				$ 248
Kentucky Utilities Co [Member] | First Mortgage Bond [Member] | First Mortgage Bond Due 2045 [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount			$ 250	$ 250
Stated interest rate			4.375%	4.375%
Maturity date				Oct. 01, 2045
Proceeds from issuance of secured debt				$ 248
At The Market Stock Offering Program [Member]
At-the-Market Stock Offering Program (Numeric) [Abstract]
Number of distribution agreements | Integer		2
Aggregate sales price of common stock based on two separate equity distribution agreements		$ 500
Shares of common stock issued during the period | shares			435,800	857,500
Average price per common share | $ / shares			$ 32.95	$ 33.33
Net proceeds from issuance of common stock			$ 14	$ 28