Accumulated Other Comprehensive Income (Loss) (After-tax Changes by Component) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (1,940)
Amounts arising during the period	(160)
Reclassifications from accumulated other comprehensive income	(46)
Net other comprehensive income during the period	(206)	58
Balance at end of period	(2,146)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(149)
Amounts arising during the period	(245)
Reclassifications from accumulated other comprehensive income
Net other comprehensive income during the period	(245)
Balance at end of period	(394)
Available For Sale Securities Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	112
Amounts arising during the period	23
Reclassifications from accumulated other comprehensive income	(1)
Net other comprehensive income during the period	22
Balance at end of period	134
Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	132
Amounts arising during the period	62
Reclassifications from accumulated other comprehensive income	(80)
Net other comprehensive income during the period	(18)
Balance at end of period	114
Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	1
Amounts arising during the period
Reclassifications from accumulated other comprehensive income
Net other comprehensive income during the period
Balance at end of period	1
Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(14)
Amounts arising during the period
Reclassifications from accumulated other comprehensive income	1
Net other comprehensive income during the period	1
Balance at end of period	(13)
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(2,023)
Amounts arising during the period
Reclassifications from accumulated other comprehensive income	34
Net other comprehensive income during the period	34
Balance at end of period	(1,989)
Defined Benefit Plans Transition Assset Obligation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	1
Amounts arising during the period
Reclassifications from accumulated other comprehensive income
Net other comprehensive income during the period
Balance at end of period	1
PPL Energy Supply LLC [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	48
Amounts arising during the period	23
Reclassifications from accumulated other comprehensive income	(26)
Net other comprehensive income during the period	(3)	(58)
Balance at end of period	45
PPL Energy Supply LLC [Member] | Available For Sale Securities Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	112
Amounts arising during the period	23
Reclassifications from accumulated other comprehensive income	(1)
Net other comprehensive income during the period	22
Balance at end of period	134
PPL Energy Supply LLC [Member] | Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	211
Amounts arising during the period
Reclassifications from accumulated other comprehensive income	(30)
Net other comprehensive income during the period	(30)
Balance at end of period	181
PPL Energy Supply LLC [Member] | Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(10)
Amounts arising during the period
Reclassifications from accumulated other comprehensive income	1
Net other comprehensive income during the period	1
Balance at end of period	(9)
PPL Energy Supply LLC [Member] | Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(265)
Amounts arising during the period
Reclassifications from accumulated other comprehensive income	4
Net other comprehensive income during the period	4
Balance at end of period	(261)
PPL Energy Supply LLC [Member] | Defined Benefit Plans Transition Assset Obligation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period
Amounts arising during the period
Reclassifications from accumulated other comprehensive income
Net other comprehensive income during the period
Balance at end of period