CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Tax effect of foreign currency translation adjustments arising during the period	$ (2)	$ 1	$ (1)	$ 0
Tax effect of available-for-sale securities arising during the period	28	(22)	15	(12)
Tax effect of qualifying derivatives arising during the period	(19)	(96)	(30)	(244)
Tax effect of equity investees' other comprehensive income (loss) arising during the period	0	0	0	0
Tax effect of defined benefit plans - prior service costs arising during period	0	(14)	0	(14)
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	0	11	0	(20)
Tax effect of defined benefit plans - net transition obligation arising during period	0	(4)	0	(4)
Tax effect of available-for-sale securities reclassified to net income	0	0	5	2
Tax effect of qualifying derivatives reclassified to net income	57	(15)	163	23
Tax effect of equity investees' other comprehensive income (loss) reclassified to net income	0	0	0	0
Tax effect of prior service costs reclassified to net income	(2)	(2)	(5)	(6)
Tax effect of net actuarial loss reclassified to net income	(4)	(4)	(14)	(10)
Tax effect of transition obligation reclassified to net income	0	0	0	(1)
PPL Energy Supply [Member]
Tax effect of foreign currency translation adjustments arising during the period	0	1	0	0
Tax effect of available-for-sale securities arising during the period	28	(22)	15	(12)
Tax effect of qualifying derivatives arising during the period	(27)	(147)	(48)	(337)
Tax effect of defined benefit plans - prior service costs arising during period	0	(9)	0	(9)
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	0	7	0	(24)
Tax effect of defined benefit plans - net transition obligation arising during period	0	(3)	0	(3)
Tax effect of available-for-sale securities reclassified to net income	0	0	5	2
Tax effect of qualifying derivatives reclassified to net income	50	(2)	153	36
Tax effect of equity investees' other comprehensive income (loss) reclassified to net income	0	0	0	0
Tax effect of prior service costs reclassified to net income	(1)	(1)	(3)	(4)
Tax effect of net actuarial loss reclassified to net income	(1)	(4)	(2)	(10)
Tax effect of transition obligation reclassified to net income	0	(1)	0	(1)
LKE [Member] | Successor [Member]
Tax effect of qualifying derivatives arising during the period	0		0
Tax effect of equity investees' other comprehensive income (loss) arising during the period	0		0
Tax effect of net actuarial loss reclassified to net income	0		1
LKE [Member] | Predecessor [Member]
Tax effect of qualifying derivatives arising during the period		(9)		(7)
Tax effect of equity investees' other comprehensive income (loss) arising during the period		1		1
Tax effect of net actuarial loss reclassified to net income		0		0
LGE [Member] | Successor [Member]
Tax effect of qualifying derivatives arising during the period	0		0
LGE [Member] | Predecessor [Member]
Tax effect of qualifying derivatives arising during the period		$ (8)		$ (7)