CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Tax effect of foreign currency translation adjustments arising during the period	$ (2)	$ 0	$ 0	$ 1
Tax effect of available-for-sale securities arising during the period	8	(1)	(20)	(13)
Tax effect of qualifying derivatives arising during the period	7	21	(55)	(11)
Tax effect of equity investees' other comprehensive income (loss) arising during the period	0	0	2	0
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	28	0	28	0
Tax effect of available-for-sale securities reclassified to net income	1	0	3	5
Tax effect of qualifying derivatives reclassified to net income	84	55	171	106
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)	(1)	(3)	(3)
Tax effect of net actuarial loss reclassified to net income	(7)	(6)	(11)	(10)
PPL Energy Supply LLC [Member]
Tax effect of available-for-sale securities arising during the period	8	(1)	(20)	(13)
Tax effect of qualifying derivatives arising during the period	5	13	(52)	(21)
Tax effect of available-for-sale securities reclassified to net income	1	0	3	5
Tax effect of qualifying derivatives reclassified to net income	75	49	168	103
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	0	(1)	(1)	(2)
Tax effect of net actuarial loss reclassified to net income	$ (2)	$ (1)	$ 0	$ (1)