Accumulated Other Comprehensive Income (Loss) (After-tax Changes by Component) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (2,728)	$ (2,274)	$ (1,565)
Amounts arising during the period	(1,080)	(575)	(754)
Reclassifications from accumulated other comprehensive income	30	145	45
Net other comprehensive income during the period	(1,050)	(430)	(709)
Distribution of PPL Energy Supply		(24)
Balance at end of period	(3,778)	(2,728)	(2,274)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(520)	(286)	(11)
Amounts arising during the period	(1,107)	(234)	(275)
Reclassifications from accumulated other comprehensive income	0	0	0
Net other comprehensive income during the period	(1,107)	(234)	(275)
Distribution of PPL Energy Supply		0
Balance at end of period	(1,627)	(520)	(286)
Available For Sale Securities Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	0	201	172
Amounts arising during the period	0	8	35
Reclassifications from accumulated other comprehensive income	0	(2)	(6)
Net other comprehensive income during the period	0	6	29
Distribution of PPL Energy Supply		(207)
Balance at end of period	0	0	201
Qualifying Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(7)	20	94
Amounts arising during the period	91	26	(10)
Reclassifications from accumulated other comprehensive income	(91)	2	(64)
Net other comprehensive income during the period	0	28	(74)
Distribution of PPL Energy Supply		(55)
Balance at end of period	(7)	(7)	20
Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	0	1	1
Amounts arising during the period	0	0	0
Reclassifications from accumulated other comprehensive income	(1)	(1)	0
Net other comprehensive income during the period	(1)	(1)	0
Distribution of PPL Energy Supply		0
Balance at end of period	(1)	0	1
Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(6)	3	(6)
Amounts arising during the period	(3)	(9)	5
Reclassifications from accumulated other comprehensive income	1	0	4
Net other comprehensive income during the period	(2)	(9)	9
Distribution of PPL Energy Supply		0
Balance at end of period	(8)	(6)	3
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(2,195)	(2,213)	(1,815)
Amounts arising during the period	(61)	(366)	(509)
Reclassifications from accumulated other comprehensive income	121	146	111
Net other comprehensive income during the period	60	(220)	(398)
Distribution of PPL Energy Supply		238
Balance at end of period	(2,135)	(2,195)	(2,213)
LG And E And KU Energy LLC [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(46)	(45)	13
Amounts arising during the period	(27)	(7)	(57)
Reclassifications from accumulated other comprehensive income	3	6	(1)
Net other comprehensive income during the period	(24)	(1)	(58)
Balance at end of period	(70)	(46)	(45)
LG And E And KU Energy LLC [Member] | Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	0	0	1
Amounts arising during the period	0	0	0
Reclassifications from accumulated other comprehensive income	(1)	0	(1)
Net other comprehensive income during the period	(1)	0	(1)
Balance at end of period	(1)	0	0
LG And E And KU Energy LLC [Member] | Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(10)	(8)	(2)
Amounts arising during the period	0	(3)	(7)
Reclassifications from accumulated other comprehensive income	2	1	1
Net other comprehensive income during the period	2	(2)	(6)
Balance at end of period	(8)	(10)	(8)
LG And E And KU Energy LLC [Member] | Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(36)	(37)	14
Amounts arising during the period	(27)	(4)	(50)
Reclassifications from accumulated other comprehensive income	2	5	(1)
Net other comprehensive income during the period	(25)	1	(51)
Balance at end of period	$ (61)	$ (36)	$ (37)