Accumulated Other Comprehensive Income (Loss) (After-tax Changes by Component) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	$ (2,311)	$ (1,429)	$ (2,274)	$ (1,565)
Amounts arising during the period	(13)	8	(69)	98
Reclassifications from accumulated other comprehensive income	64	23	83	69
Net other comprehensive income during the period	51	31	14	167
Distribution of PPL Energy Supply	(24)		(24)
Balance at end of period	(2,284)	(1,398)	(2,284)	(1,398)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(352)	120	(286)	(11)
Amounts arising during the period	(83)	(3)	(149)	128
Reclassifications from accumulated other comprehensive income	0	0	0	0
Net other comprehensive income during the period	(83)	(3)	(149)	128
Distribution of PPL Energy Supply	0		0
Balance at end of period	(435)	117	(435)	117
Available For Sale Securities Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	206	177	202	173
Amounts arising during the period	2	14	7	19
Reclassifications from accumulated other comprehensive income	(1)	(1)	(2)	(2)
Net other comprehensive income during the period	1	13	5	17
Distribution of PPL Energy Supply	(207)		(207)
Balance at end of period	0	190	0	190
Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	9	67	20	94
Amounts arising during the period	21	(1)	27	(47)
Reclassifications from accumulated other comprehensive income	27	(5)	10	14
Net other comprehensive income during the period	48	(6)	37	(33)
Distribution of PPL Energy Supply	(55)		(55)
Balance at end of period	2	61	2	61
Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	0	1	1	1
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	0	0	(1)	0
Net other comprehensive income during the period	0	0	(1)	0
Distribution of PPL Energy Supply	0		0
Balance at end of period	0	1	0	1
Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	3	(5)	3	(6)
Amounts arising during the period	(6)	0	(6)	0
Reclassifications from accumulated other comprehensive income	0	1	0	2
Net other comprehensive income during the period	(6)	1	(6)	2
Distribution of PPL Energy Supply	0		0
Balance at end of period	(3)	(4)	(3)	(4)
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(2,178)	(1,790)	(2,215)	(1,817)
Amounts arising during the period	53	(2)	52	(2)
Reclassifications from accumulated other comprehensive income	38	28	76	55
Net other comprehensive income during the period	91	26	128	53
Distribution of PPL Energy Supply	238		238
Balance at end of period	(1,849)	(1,764)	(1,849)	(1,764)
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
Distribution of PPL Energy Supply	0		0
Balance at end of period	1	1	1	1
LG And E And KU Energy LLC [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(45)	12	(45)	13
Amounts arising during the period	(8)	(2)	(8)	(2)
Reclassifications from accumulated other comprehensive income	1		1	(1)
Net other comprehensive income during the period	(7)	(2)	(7)	(3)
Balance at end of period	(52)	10	(52)	10
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	(1)	0	0	1
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	0		(1)	(1)
Net other comprehensive income during the period	0	0	(1)	(1)
Balance at end of period	(1)	0	(1)	0
LG And E And KU Energy LLC [Member] | Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(8)	(2)	(8)	(2)
Amounts arising during the period	0	0	0	0
Reclassifications from accumulated other comprehensive income	1		1	0
Net other comprehensive income during the period	1	0	1	0
Balance at end of period	(7)	(2)	(7)	(2)
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)	14	(37)	14
Amounts arising during the period	(8)	(2)	(8)	(2)
Reclassifications from accumulated other comprehensive income	0		1	0
Net other comprehensive income during the period	(8)	(2)	(7)	(2)
Balance at end of period	(44)	12	(44)	12
LG And E And KU Energy 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
Net other comprehensive income during the period	0	0	0	0
Balance at end of period	$ 0	$ 0	$ 0	$ 0