Accumulated Other Comprehensive Income (Loss) (After-tax Changes by Component) (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
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	$ (1,398)	$ (2,128)	$ (1,565)	$ (1,940)
Amounts arising during the period	(55)	93	43	(48)
Reclassifications from accumulated other comprehensive income	15	28	84	(19)
Net other comprehensive income during the period	(40)	121	127	(67)
Balance at end of period	(1,438)	(2,007)	(1,438)	(2,007)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	117	(401)	(11)	(149)
Amounts arising during the period	(48)	87	80	(165)
Reclassifications from accumulated other comprehensive income	0	0	0	0
Net other comprehensive income during the period	(48)	87	80	(165)
Balance at end of period	69	(314)	69	(314)
Available For Sale Securities Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	190	135	173	112
Amounts arising during the period	(1)	15	18	40
Reclassifications from accumulated other comprehensive income	(3)	0	(5)	(2)
Net other comprehensive income during the period	(4)	15	13	38
Balance at end of period	186	150	186	150
Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	61	102	94	132
Amounts arising during the period	(5)	(9)	(52)	77
Reclassifications from accumulated other comprehensive income	(12)	(6)	2	(122)
Net other comprehensive income during the period	(17)	(15)	(50)	(45)
Balance at end of period	44	87	44	87
Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	1	1	1	1
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	0	(1)	0	(1)
Net other comprehensive income during the period	0	(1)	0	(1)
Balance at end of period	1	0	1	0
Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(4)	(11)	(6)	(14)
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	1	2	3	5
Net other comprehensive income during the period	1	2	3	5
Balance at end of period	(3)	(9)	(3)	(9)
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(1,764)	(1,955)	(1,817)	(2,023)
Amounts arising during the period	(1)	0	(3)	0
Reclassifications from accumulated other comprehensive income	29	33	84	101
Net other comprehensive income during the period	28	33	81	101
Balance at end of period	(1,736)	(1,922)	(1,736)	(1,922)
Defined Benefit Plans Transition Assset Obligation [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	1	1	1	1
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	0	0	0	0
Net other comprehensive income during the period	0	0	0	0
Balance at end of period	1	1	1	1
PPL Energy Supply LLC [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	85	14	77	48
Amounts arising during the period	(1)	15	18	40
Reclassifications from accumulated other comprehensive income	(6)	(25)	(17)	(84)
Net other comprehensive income during the period	(7)	(10)	1	(44)
Balance at end of period	78	4	78	4
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	190	135	173	112
Amounts arising during the period	(1)	15	18	40
Reclassifications from accumulated other comprehensive income	(3)	0	(5)	(2)
Net other comprehensive income during the period	(4)	15	13	38
Balance at end of period	186	150	186	150
PPL Energy Supply LLC [Member] | Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	75	144	88	211
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	(5)	(29)	(18)	(96)
Net other comprehensive income during the period	(5)	(29)	(18)	(96)
Balance at end of period	70	115	70	115
PPL Energy Supply LLC [Member] | Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(3)	(8)	(4)	(10)
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	1	1	2	3
Net other comprehensive income during the period	1	1	2	3
Balance at end of period	(2)	(7)	(2)	(7)
PPL Energy Supply LLC [Member] | Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(177)	(257)	(180)	(265)
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	1	3	4	11
Net other comprehensive income during the period	1	3	4	11
Balance at end of period	(176)	(254)	(176)	(254)
PPL Energy Supply LLC [Member] | Defined Benefit Plans Transition Assset Obligation [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	0	0	0	0
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	0	0	0	0
Net other comprehensive income during the period	0	0	0	0
Balance at end of period	$ 0	$ 0	$ 0	$ 0