Accumulated Other Comprehensive Income (Loss) (Income (Expense) Effect of Reclassifications) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	$ 976	$ 1,208
Energy purchases	(691)	(883)
Other Income (Expense) - net	122	(17)
Interest Expense	(251)	(230)
Income (Loss) Before Income Taxes	564	804
Income Taxes	(151)	(259)
Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Net Income Available to PPL	46
Available For Sale Securities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing
Energy purchases
Other Income (Expense) - net	2
Interest Expense
Income (Loss) Before Income Taxes	2
Income Taxes	(1)
Net Income Available to PPL	1
Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	67
Energy purchases	(16)
Other Income (Expense) - net	69
Interest Expense	(5)
Income (Loss) Before Income Taxes	115
Income Taxes	(35)
Net Income Available to PPL	80
Qualifying Derivatives [Member] | Interest Rate Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing
Energy purchases
Other Income (Expense) - net
Interest Expense	(5)
Income (Loss) Before Income Taxes	(5)
Income Taxes	2
Net Income Available to PPL	(3)
Qualifying Derivatives [Member] | Cross Currency Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing
Energy purchases
Other Income (Expense) - net	69
Interest Expense
Income (Loss) Before Income Taxes	69
Income Taxes	(17)
Net Income Available to PPL	52
Qualifying Derivatives [Member] | Energy Commodities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	67
Energy purchases	(16)
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	51
Income Taxes	(20)
Net Income Available to PPL	31
Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(49)
Income Taxes	14
Net Income Available to PPL	(35)
Defined Benefit Plans [Member] | Prior Service Costs [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(2)
Income Taxes	1
Net Income Available to PPL	(1)
Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(47)
Income Taxes	13
Net Income Available to PPL	(34)
PPL Energy Supply LLC [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	976	1,208
Energy purchases	(434)	(659)
Other Income (Expense) - net	4	5
Interest Expense	(46)	(37)
Income (Loss) Before Income Taxes	(73)	486
Income Taxes	35	(177)
PPL Energy Supply LLC [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Net Income Available to PPL	26
PPL Energy Supply LLC [Member] | Available For Sale Securities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing
Energy purchases
Other Income (Expense) - net	2
Interest Expense
Income (Loss) Before Income Taxes	2
Income Taxes	(1)
Net Income Available to PPL	1
PPL Energy Supply LLC [Member] | Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	67
Energy purchases	(16)
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	51
Income Taxes	(21)
Net Income Available to PPL	30
PPL Energy Supply LLC [Member] | Qualifying Derivatives [Member] | Energy Commodities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Wholesale energy marketing	67
Energy purchases	(16)
Other Income (Expense) - net
Interest Expense
Income (Loss) Before Income Taxes	51
Income Taxes	(21)
Net Income Available to PPL	30
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(8)
Income Taxes	3
Net Income Available to PPL	(5)
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Prior Service Costs [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(2)
Income Taxes	1
Net Income Available to PPL	(1)
PPL Energy Supply LLC [Member] | Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Income (Loss) Before Income Taxes	(6)
Income Taxes	2
Net Income Available to PPL	$ (4)