Financing Activities (Short-term Debt) (Details) (Commercial Paper [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Jun. 30, 2013	Dec. 31, 2012
Short-term Debt [Line Items]
Capacity	$ 1,750
Commercial paper issuances	212			481
Unused capacity	1,538
PPL Energy Supply [Member]
Short-term Debt [Line Items]
Weighted-average interest rate				0.50%
Capacity	750
Commercial paper issuances				356
Unused capacity	750
PPL Electric [Member]
Short-term Debt [Line Items]
Capacity	300
Unused capacity	300
LGE [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	72			55
Unused capacity	278
KU [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	140			70
Unused capacity	210
PPL Energy Supply LLC [Member]
Short-term Debt [Line Items]
Weighted-average interest rate				0.50%
Capacity	750
Commercial paper issuances				356
Unused capacity	750
PPL Electric Utilities Corp [Member]
Short-term Debt [Line Items]
Capacity	300
Unused capacity	300
LG And E And KU Energy LLC [Member] | LGE [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	72			55
Unused capacity	278
LG And E And KU Energy LLC [Member] | KU [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	140			70
Unused capacity	210
Louisville Gas And Electric Co [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	72			55
Unused capacity	278
Kentucky Utilities Co [Member]
Short-term Debt [Line Items]
Weighted-average interest rate	0.28%			0.42%
Capacity	350	[1]	250
Commercial paper issuances	140			70
Unused capacity	$ 210

[1] In April 2013, the capacity was increased from $250 million.