Accumulated Other Comprehensive Income (Loss) (Income (Expense) Effect of Reclassifications) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Affected Line Item on the Statements of Income [Line Items]
Depreciation	$ (307)	$ (284)	$ (913)	$ (845)
Other Income (Expense) - net	144	(117)	38	18
Interest Expense	(258)	(244)	(775)	(747)
Total Pre-tax	755	485	1,552	1,528
Income Taxes	(265)	(81)	(520)	(329)
Total After-Tax	490	404	1,032	1,199
Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total After-Tax	(15)	(28)	(84)	19
Available For Sale Securities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Other Income (Expense) - net	7	1	11	4
Total Pre-tax	7	1	11	4
Income Taxes	(4)	(1)	(6)	(2)
Total After-Tax	3	0	5	2
Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total Pre-tax	15	17	2	190
Income Taxes	(3)	(11)	(4)	(68)
Total After-Tax	12	6	(2)	122
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]
Interest Expense	(5)	(5)	(12)	(14)
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]
Other Income (Expense) - net	12	(25)	(17)	45
Interest Expense	0	(1)	1	0
Qualifying Derivatives [Member] | Energy Commodities [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Unregulated wholesale energy	(2)	54	(1)	178
Energy purchases	8	(11)	23	(41)
Discontinued operations	1	4	6	20
Other	1	1	2	2
Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total Pre-tax	(40)	(48)	(116)	(146)
Income Taxes	10	13	29	40
Total After-Tax	(30)	(35)	(87)	(106)
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]
Total Pre-tax	(2)	(3)	(6)	(8)
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]
Total Pre-tax	(38)	(45)	(110)	(138)
Equity Investees Accumulated Other Comprehensive Income [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Other Income (Expense) - net	0	1	0	1
Total Pre-tax	0	1	0	1
Income Taxes	0	0	0	0
Total After-Tax	0	1	0	1
PPL Energy Supply LLC [Member]
Affected Line Item on the Statements of Income [Line Items]
Depreciation	(74)	(75)	(225)	(223)
Other Income (Expense) - net	10	1	23	17
Interest Expense	(31)	(37)	(95)	(123)
Total Pre-tax	168	190	54	236
Income Taxes	(74)	(71)	(16)	(91)
Total After-Tax	94	119	38	145
PPL Energy Supply LLC [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total After-Tax	6	25	17	84
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]
Other Income (Expense) - net	7	1	11	4
Total Pre-tax	7	1	11	4
Income Taxes	(4)	(1)	(6)	(2)
Total After-Tax	3	0	5	2
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]
Total Pre-tax	7	48	29	159
Income Taxes	(2)	(19)	(11)	(63)
Total After-Tax	5	29	18	96
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]
Unregulated wholesale energy	(2)	54	(1)	178
Energy purchases	8	(11)	23	(41)
Discontinued operations	1	4	6	20
Other	0	1	1	2
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]
Total Pre-tax	(3)	(7)	(10)	(23)
Income Taxes	1	3	4	9
Total After-Tax	(2)	(4)	(6)	(14)
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]
Total Pre-tax	(2)	(2)	(4)	(5)
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]
Total Pre-tax	$ (1)	$ (5)	$ (6)	$ (18)