Segment and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011
Income Statement Data
Revenues from external customers	$ 2,549		$ 2,489		$ 6,661		$ 5,399
Net Income Attributable to PPL	271		196		812		597
Balance Sheet Data
Assets	43,508				43,508				42,648
Kentucky Regulated [Member]
Income Statement Data
Revenues from external customers	658		638		1,363		1,404
Net Income Attributable to PPL	34		31		76		106
Balance Sheet Data
Assets	10,288				10,288				10,229
UK Regulated [Member]
Income Statement Data
Revenues from external customers	557		420		1,119		645
Net Income Attributable to PPL	196		38		361		93
Balance Sheet Data
Assets	13,445				13,445				13,364
Pennsylvania Regulated [Member]
Income Statement Data
Revenues from external customers	403		436		860		990
Intersegment electric revenues	1		4		2		8
Net Income Attributable to PPL	29		36		62		88
Balance Sheet Data
Assets	5,532				5,532				5,610
Supply [Member]
Income Statement Data
Revenues from external customers	931	[1]	995	[1]	3,319	[1]	2,360	[1]
Intersegment electric revenues	17		4		38		10
Net Income Attributable to PPL	12	[1]	91	[1]	313	[1]	310	[1]
Balance Sheet Data
Assets	$ 14,243				$ 14,243				$ 13,445

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