CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Tax effect of foreign currency translation adjustments arising during the period	$ (4)	$ 1	$ (8)
Tax effect of available-for-sale securities arising during the period	0	(9)	(39)
Tax effect of qualifying derivatives arising during the period	(18)	0	23
Tax effect of defined benefit plans - prior service costs arising during period	2	6	(4)
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	40	67	225
Tax effect of available-for-sale securities reclassified to net income	0	2	7
Tax effect of qualifying derivatives reclassified to net income	21	(15)	23
Tax effect of equity investees' other comprehensive (income) loss reclassified to net income	0	0	0
Tax effect of prior service costs reclassified to net income	(1)	0	(3)
Tax effect of net actuarial loss reclassified to net income	(35)	(46)	(34)
LG And E And KU Energy LLC [Member]
Tax effect of defined benefit plans - prior service costs arising during period	0	(2)	(4)
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	18	2	32
Tax effect of equity investees' other comprehensive (income) loss reclassified to net income	0	0	0
Tax effect of prior service costs reclassified to net income	1	1	0
Tax effect of net actuarial loss reclassified to net income	$ 1	$ 3	$ 0