Segment and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011		Dec. 31, 2011
Income Statement Data
Revenues from external customers	$ 4,112		$ 2,910
Net Income Attributable to PPL	541		401
Balance Sheet Data
Assets	44,082				42,648
Kentucky Regulated [Member]
Income Statement Data
Revenues from external customers	705		766
Net Income Attributable to PPL	42		75
Balance Sheet Data
Assets	10,225	[1]			10,229	[1]
UK Regulated [Member]
Income Statement Data
Revenues from external customers	562		225
Net Income Attributable to PPL	165		55
Balance Sheet Data
Assets	13,779				13,364
Pennsylvania Regulated [Member]
Income Statement Data
Revenues from external customers	457		554
Intersegment revenues	1		4
Net Income Attributable to PPL	33		52
Balance Sheet Data
Assets	5,600				5,610
Supply [Member]
Income Statement Data
Revenues from external customers	2,388	[2]	1,365	[2]
Intersegment revenues	21		6
Net Income Attributable to PPL	301	[2]	219	[2]
Balance Sheet Data
Assets	$ 14,478	[1]			$ 13,445	[1]

[1] A portion of the goodwill related to the 2010 LKE acquisition has been attributed to PPL's supply segment.

[2] Includes unrealized gains and losses from economic activity. See Note 14 for additional information.