Accumulated Other Comprehensive Income (Loss) (Income (Expense) Effect of Reclassifications) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	$ 811	$ 1,083	$ 1,787	$ 2,291
Energy purchases	(572)	(787)	(1,263)	(1,670)
Depreciation	(286)	(271)	(570)	(535)
Other Income (Expense) - net	13	30	135	13
Interest Expense	(258)	(236)	(509)	(466)
Income (Loss) Before Income Taxes	513	365	1,077	1,169
Income Taxes	(109)	(88)	(260)	(347)
Income from Continuing Operations After Income Taxes	404	277	817	822
Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income from Continuing Operations After Income Taxes	1		47
Available For Sale Securities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing
Energy purchases
Depreciation
Other Income (Expense) - net	1		3
Interest Expense
Income (Loss) Before Income Taxes	1		3
Income Taxes			(1)
Income from Continuing Operations After Income Taxes	1		2
Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	73		140
Energy purchases	(14)		(30)
Depreciation	(1)		1
Other Income (Expense) - net	1		70
Interest Expense	(3)		(8)
Income (Loss) Before Income Taxes	58		173
Income Taxes	(22)		(57)
Income from Continuing Operations After Income Taxes	36		116
Qualifying Derivatives [Member] | Interest Rate Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing
Energy purchases
Depreciation
Other Income (Expense) - net
Interest Expense	(4)		(9)
Income (Loss) Before Income Taxes	(4)		(9)
Income Taxes	2		4
Income from Continuing Operations After Income Taxes	(2)		(5)
Qualifying Derivatives [Member] | Cross Currency Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing
Energy purchases
Depreciation
Other Income (Expense) - net	1		70
Interest Expense	1		1
Income (Loss) Before Income Taxes	2		71
Income Taxes			(17)
Income from Continuing Operations After Income Taxes	2		54
Qualifying Derivatives [Member] | Energy Commodities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	73		140
Energy purchases	(14)		(30)
Depreciation	1		1
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	60		111
Income Taxes	(24)		(44)
Income from Continuing Operations After Income Taxes	36		67
Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(49)		(98)
Income Taxes	13		27
Income from Continuing Operations After Income Taxes	(36)		(71)
Defined Benefit Plans [Member] | Prior Service Costs [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(3)		(5)
Income Taxes	1		2
Income from Continuing Operations After Income Taxes	(2)		(3)
Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(46)		(93)
Income Taxes	12		25
Income from Continuing Operations After Income Taxes	(34)		(68)
PPL Energy Supply LLC [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	811	1,083	1,787	2,291
Energy purchases	(418)	(635)	(852)	(1,294)
Depreciation	(79)	(69)	(157)	(133)
Other Income (Expense) - net	12	6	16	11
Interest Expense	(46)	(43)	(92)	(80)
Income (Loss) Before Income Taxes	153	28	80	514
Income Taxes	(67)	(9)	(32)	(186)
PPL Energy Supply LLC [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income from Continuing Operations After Income Taxes	33		59
PPL Energy Supply LLC [Member] | Available For Sale Securities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing
Energy purchases
Depreciation
Other Income (Expense) - net	1		3
Interest Expense
Income (Loss) Before Income Taxes	1		3
Income Taxes			(1)
Income from Continuing Operations After Income Taxes	1		2
PPL Energy Supply LLC [Member] | Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	73		140
Energy purchases	(14)		(30)
Depreciation	1		1
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	60		111
Income Taxes	(23)		(44)
Income from Continuing Operations After Income Taxes	37		67
PPL Energy Supply LLC [Member] | Qualifying Derivatives [Member] | Energy Commodities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Wholesale energy marketing	73		140
Energy purchases	(14)		(30)
Depreciation	1		1
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	60		111
Income Taxes	(23)		(44)
Income from Continuing Operations After Income Taxes	37		67
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(8)		(16)
Income Taxes	3		6
Income from Continuing Operations After Income Taxes	(5)		(10)
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Prior Service Costs [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(1)		(3)
Income Taxes			1
Income from Continuing Operations After Income Taxes	(1)		(2)
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) Before Income Taxes	(7)		(13)
Income Taxes	3		5
Income from Continuing Operations After Income Taxes	$ (4)		$ (8)