Income and Other Taxes (Income Tax Expense and Reconciliation of Income Tax Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Income Tax Expense (Benefit)
Current - Federal	$ 43		$ (91)		$ (15)
Current - State	30		(4)		(5)
Current - Foreign	152		181		121
Total Current Expense (Benefit)	225		86		101
Deferred - Federal	345		75		547
Deferred - State	136		45		100
Deferred - Foreign	96		(53)		35
Total Deferred Expense (Benefit), excluding operating loss carry forwards	577		67		682
Investment tax credit, net - Federal	(7)		(8)		(10)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	8		36	[1]	(195)	[1]
Deferred - State	(22)		(18)		(60)
Total Tax Expense (Benefit) of Operating Loss Carryforwards	(14)		18		(255)
Total income tax from continuing operations	781		163		518
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	389		12		327
Total income tax expense (benefit) - State	144		23		35
Total income tax expense - Foreign	248		128		156
Total income tax from continuing operations	781		163		518
Discontinued operations	109		18		23
Stock-based compensation recorded to Additional Paid-in Capital	(4)		(2)		(1)
Valuation allowance on state deferred taxes related to issuance costs of Purchase Contracts recorded to Additional Paid-in Capital	0		(2)		0
Other comprehensive income	190		159		(526)
Valuation allowance on state deferred taxes recorded to other comprehensive income	0		(7)		0
Total income tax expense (benefits) excluded from incomes taxes from continuing operations	295		166		(504)
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	827		441		703
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	41		(9)		25
State valuation allowance adjustments	55	[2]	24	[2]	13
Impact of lower U.K. income tax rates	(167)	[3]	(129)	[3]	(110)	[3]
U.S. income tax on foreign earnings - net of foreign tax credit	53	[4]	9	[4]	26	[4]
Federal and state tax reserve adjustments	(1)		(43)	[5]	(1)	[5]
Federal and state income tax return adjustments	2		(5)		16	[6]
Impact of the United Kingdom Finance Acts on deferred tax balances	(1)	[3]	(97)	[3]	(75)	[3]
Federal income tax credits	(1)		(9)	[7]	(11)	[7]
Depreciation not normalized	(7)		(8)		(11)
State deferred tax rate change	(1)	[8]	15	[8]	(19)	[8]
Intercompany interest on United Kingdom financing entities	(8)		(10)		(9)
Other	(11)		(16)		(29)
Total increase (decrease)	(46)		(278)		(185)
Total income tax from continuing operations	781		163		518
Effective income tax rate	33.00%		12.90%		25.80%
Adjustment to valuation allowance on deferred tax assets due to spinoff anouncement	50
Expense related to a deferred tax valuation allowance due to a decrease in projected future taxable income			23
United Kingdom statutory income tax rate in effect during period prior to a change	21.00%		23.00%		25.00%
United Kingdom statutory income tax rate reduction			24.00%		24.00%
United Kingdom statutory income tax rate reduction in 2015	20.00%
Expense from increased taxable dividends	47		25
Expense (benefit) related to the recalculation of 2010 United Kingdom earnings and profits			(19)		23
Benefit from favorable United States Tax Court decision on deductibility of United Kingdom windfall profit tax	42
Expense from reversal by United States Court of Appeals for the Third Circuit on deductibility of United Kingdom windfall profit tax	39
Benefit from favorable United States Tax Court decision on deductibility of United Kingdom windfall profit tax			44
Interest portion of benefit from favorable United States Tax Court decision on deductibility of United Kingdom windfall profit tax			19
Benefit recorded related to stranded cost securitization included in change in federal and state income tax reserves			7		6
Reversal of prior years' state income tax benefit related to regulated depreciation	5				16
Benefit related to 2010 federal and state tax return adjustments related to domestic manufacturing deduction					5
Taxes, other than income
State gross receipts	147		135		135
Foreign property	157		147		147
Domestic property and other	70		69		70
Total	374		351		352
PPL Energy Supply LLC [Member]
Income Tax Expense (Benefit)
Current - Federal	28		118		74
Current - State	13		16		19
Total Current Expense (Benefit)	41		134		93
Deferred - Federal	66		(285)		187
Deferred - State	11		(27)		7
Total Deferred Expense (Benefit), excluding operating loss carry forwards	77		(312)		194
Investment tax credit, net - Federal	(2)		(3)		(2)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	0		22	[1]	(48)	[1]
Deferred - State	0		0		(1)
Total Tax Expense (Benefit) of Operating Loss Carryforwards	0		22		(49)
Total income tax from continuing operations	116	[9]	(159)	[9]	236	[9]
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	92		(148)		211
Total income tax expense (benefit) - State	24		(11)		25
Total income tax from continuing operations	116	[9]	(159)	[9]	236	[9]
Discontinued operations	109		17		27
Other comprehensive income	(56)		47		(267)
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	106		(147)		233
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	17		(24)		30
Federal income tax credits	0		(8)	[10]	(11)	[10]
State deferred tax rate change	(1)	[11]	15	[11]	(19)	[11]
Other	(6)		5		3
Total increase (decrease)	10		(12)		3
Total income tax from continuing operations	116	[9]	(159)	[9]	236	[9]
Effective income tax rate	38.30%		37.90%		35.50%
Taxes, other than income
State gross receipts	45		37		35
State capital stock	1		1		5
Domestic property and other	11		15		15
Total	57		53		55
PPL Electric Utilities Corp [Member]
Income Tax Expense (Benefit)
Current - Federal	60		(15)		(28)
Current - State	15		(4)		(18)
Total Current Expense (Benefit)	75		(19)		(46)
Deferred - Federal	70		109		162
Deferred - State	16		16		42
Total Deferred Expense (Benefit), excluding operating loss carry forwards	86		125		204
Investment tax credit, net - Federal	(1)		(1)		(1)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	0		4		(72)
Deferred - State	0		(1)		(17)
Total Tax Expense (Benefit) of Operating Loss Carryforwards	0		3		(89)
Total income tax from continuing operations	160		108		68
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	129		97		61
Total income tax expense (benefit) - State	31		11		7
Total income tax from continuing operations	160		108		68
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	148		111		71
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	22		16		9
Federal and state tax reserve adjustments	(1)		(9)	[12]	(8)	[12]
Federal and state income tax return adjustments	1	[13]	(1)	[13]	7	[13]
Depreciation not normalized	(6)		(6)		(8)
Other	(4)		(3)		(3)
Total increase (decrease)	12		(3)		(3)
Total income tax from continuing operations	160		108		68
Effective income tax rate	37.80%		34.10%		33.30%
Benefit recorded related to stranded cost securitization included in change in federal and state income tax reserves			7		6
Reversal of prior years' state income tax benefit related to regulated depreciation	(5)				5
Taxes, other than income
State gross receipts	102		98		101
Domestic property and other	5		5		4
Total	107		103		105
LG And E And KU Energy LLC [Member]
Income Tax Expense (Benefit)
Current - Federal	(247)		(59)		(32)
Current - State	8		10		2
Total Current Expense (Benefit)	(239)		(49)		(30)
Deferred - Federal	437		244		185
Deferred - State	23		20		15
Total Deferred Expense (Benefit), excluding operating loss carry forwards	460		264		200
Investment tax credit, net - Federal	(4)		(4)		(6)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	(8)		(4)		(46)
Deferred - State	0		(1)		(12)
Total Tax Expense (Benefit) of Operating Loss Carryforwards	(8)		(5)		(58)
Total income tax from continuing operations	209	[14]	206	[14]	106	[14]
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	178		177		101
Total income tax expense (benefit) - State	31		29		5
Total income tax from continuing operations	209	[14]	206	[14]	106	[14]
Discontinued operations	1		1		(4)
Other comprehensive income	(36)		18		(12)
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	194		193		116
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	20		20		6
Amortization of investment tax credit	(4)		(4)		(6)
Net operating loss carryforward adjustments	0		0		(9)	[15]
Other	(1)		(3)		(1)
Total increase (decrease)	15		13		(10)
Total income tax from continuing operations	209	[14]	206	[14]	106	[14]
Effective income tax rate	37.80%		37.40%		32.00%
Taxes, other than income
Domestic property and other	52		48		46
Total	52		48		46
Louisville Gas And Electric Co [Member]
Income Tax Expense (Benefit)
Current - Federal	(25)		52		(2)
Current - State	10		16		3
Total Current Expense (Benefit)	(15)		68		1
Deferred - Federal	114		33		65
Deferred - State	6		(2)		6
Total Deferred Expense (Benefit), excluding operating loss carry forwards	120		31		71
Investment tax credit, net - Federal	(2)		(2)		(3)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	0		(3)		0
Total Tax Expense (Benefit) of Operating Loss Carryforwards	0		(3)		0
Total income tax from continuing operations	103		94		69
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	87		80		60
Total income tax expense (benefit) - State	16		14		9
Total income tax from continuing operations	103		94		69
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	95		90		67
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	10		10		5
Amortization of investment tax credit	(2)		(2)		(3)
Other	0		(4)		0
Total increase (decrease)	8		4		2
Total income tax from continuing operations	103		94		69
Effective income tax rate	37.90%		36.60%		35.90%
Taxes, other than income
Domestic property and other	25		24		23
Total	25		24		23
Kentucky Utilities Co [Member]
Income Tax Expense (Benefit)
Current - Federal	(95)		51		(20)
Current - State	6		12		(1)
Total Current Expense (Benefit)	(89)		63		(21)
Deferred - Federal	212		66		111
Deferred - State	14		8		11
Total Deferred Expense (Benefit), excluding operating loss carry forwards	226		74		122
Investment tax credit, net - Federal	(2)		(2)		(3)
Tax expense (benefit) of operating loss carryforwards [Abstract]
Deferred - Federal	0		(3)		(20)
Total Tax Expense (Benefit) of Operating Loss Carryforwards	0		(3)		(20)
Total income tax from continuing operations	135	[16]	132	[16]	78	[16]
Income tax expense (benefit) from continuing operations [Abstract]
Total income tax expense - Federal	115		112		68
Total income tax expense (benefit) - State	20		20		10
Total income tax from continuing operations	135	[16]	132	[16]	78	[16]
Other comprehensive income	(1)		(1)		1
Reconciliation of Income Tax Expense
Federal income tax on Income (Loss) from Continuing Operations Before Income Taxes at statutory tax rate - 35%	124		126		75
Federal statutory rate	35.00%		35.00%		35.00%
Increase (decrease) due to:
State income taxes, net of federal income tax benefit	13		14		6
Amortization of investment tax credit	(2)		(2)		(3)
Other	0		(6)		0
Total increase (decrease)	11		6		3
Total income tax from continuing operations	135	[16]	132	[16]	78	[16]
Effective income tax rate	38.00%		36.70%		36.30%
Taxes, other than income
Domestic property and other	27		24		23
Total	$ 27		$ 24		$ 23

[1] A 2012Federal income tax return adjustment was recorded in 2013related to a reduction in the 2012 NOL recorded in the filed return. The reduction was primarily due to PPL's decision, at the time of filing, to utilize regular modified accelerated cost recovery system (MACRS) depreciation rates for certain non-regulated assets otherwise eligible for bonus tax depreciation.

[2] As a result of the PPL Energy Supply spinoff announcement, PPL recorded $50 million deferred income tax expense during 2014 to adjust the valuation allowance on deferred tax assets primarily for state net operating loss carryforwards that were previously supported by the future earnings of PPL Energy Supply. See Note 8 for additional information on the anticipated spinoff. During 2013, PPL recorded $23 million of state deferred income tax expense related to a deferred tax valuation allowance primarily due to a decrease in projected future taxable income at PPL Energy Supply over the remaining carryforward period of Pennsylvania net operating losses.

[3] The U.K. Finance Act 2013, enacted in July 2013, reduced the U.K. statutory income tax rate from 23% to 21% effective April 1, 2014 and from 21% to 20% effective April 1, 2015. As a result, PPL reduced its net deferred tax liabilities and recognized a deferred tax benefit during 2013 related to both rate decreases. The U.K. Finance Act 2012, enacted in July 2012, reduced the U.K. statutory income tax rate from 25% to 24% retroactive to April 1, 2012 and from 24% to 23% effective April 1, 2013. As a result, PPL reduced its net deferred tax liabilities and recognized a deferred tax benefit during 2012 related to both rate decreases.

[4] During 2014, PPL recorded $47 million of income tax expense primarily attributable to taxable dividends. During 2013, PPL recorded $28 million of income tax expense resulting from increased taxable dividends offset by a $19 million income tax benefit associated with a ruling obtained from the IRS impacting the recalculation of 2010 U.K. earnings and profits that was reflected on an amended 2010 U.S. tax return. During 2012, PPL recorded a $23 million adjustment to federal income tax expense related to the recalculation of 2010 U.K. earnings and profits.

[5] In 1997, the U.K. imposed a Windfall Profits Tax (WPT) on privatized utilities, including WPD. PPL filed its federal income tax returns for years subsequent to its 1997 and 1998 claims for refund on the basis that the U.K. WPT was creditable. In September 2010, the U.S. Tax Court (Tax Court) ruled in PPL’s favor in a dispute with the IRS, concluding that the U.K. WPT is a creditable tax for U.S. tax purposes. As a result, and with the finalization of other issues, PPL recorded a $42 million tax benefit in 2010. In January 2011, the IRS appealed the Tax Court’s decision to the U.S. Court of Appeals for the Third Circuit (Third Circuit). In December 2011, the Third Circuit issued its opinion reversing the Tax Court’s decision, holding that the U.K. WPT is not a creditable tax. As a result of the Third Circuit’s adverse determination, PPL recorded a $39 million expense in 2011. In June 2012, the U.S. Court of Appeals for the Fifth Circuit issued a contrary opinion in an identical case involving another company. In July 2012, PPL filed a petition for a writ of certiorari seeking U.S. Supreme Court review of the Third Circuit’s opinion. The Supreme Court granted PPL’s petition and oral argument was held in February 2013. On May 20, 2013, the Supreme Court reversed the Third Circuit’s opinion and ruled that the WPT is a creditable tax. As a result of the Supreme Court ruling, PPL recorded a tax benefit of $44 million during 2013, of which $19 million relates to interest. PPL recorded a tax benefit of $7 million during 2013 and $6 million during 2012 federal and state income tax reserves related to stranded cost securitization. The reserve balance at December 31, 2013 related to stranded costs securitization was zero.

[6] During 2012, PPL recorded $16 million in federal and state income tax expense related to the filing of the 2011 federal and state income tax returns. Of this amount, $5 million relates to the reversal of prior years’ state income tax benefits related to regulated depreciation. PPL changed its method of accounting for repair expenditures for tax purposes effective for its 2008 tax year. In August 2011, the IRS issued guidance regarding the use and evaluation of statistical samples and sampling estimates for network assets. The IRS guidance provided a safe harbor method of determining whether the repair expenditures for electric transmission and distribution property can be currently deducted for tax purposes. PPL adopted the safe harbor method with the filing of its 2011 federal income tax return.

[7] During 2013 and 2012, PPL recorded deferred tax benefits related to investment tax credits on progress expenditures for the Holtwood hydroelectric plant expansion. See Note 8 for additional information.

[8] During 2014, 2013 and 2012, PPL recorded adjustments related to its December 31 state deferred tax liabilities as a result of annual changes in state apportionment and the impact on the future estimated state income tax rate.

[9] Excludes current and deferred federal and state tax expense recorded to Discontinued Operations of $109 million, $17 million and $27 million in 2014, 2013 and 2012. Also excludes federal and state tax expense (benefit) recorded to OCI of $(56) million, $47 million and $(267) million in 2014, 2013 and 2012.

[10] During 2013 and 2012, PPL Energy Supply recorded deferred tax benefits related to investment tax credits on progress expenditures for the Holtwood hydroelectric plant expansion. See Note 8 for additional information.

[11] During 2014, 2013 and 2012, PPL Energy Supply recorded adjustments related to its December 31 state deferred tax liabilities as a result of annual changes in state apportionment and the impact on the future estimated state income tax rate.

[12] PPL Electric recorded a tax benefit of $7 million during 2013 and $6 million during 2012 to federal and state income tax reserves related to stranded cost securitization. The reserve balance at December 31, 2013 related to stranded costs securitization was zero.

[13] PPL Electric changed its method of accounting for repair expenditures for tax purposes effective for its 2008 tax year. In August 2011, the IRS issued guidance regarding the use and evaluation of statistical samples and sampling estimates for network assets. The IRS guidance provided a safe harbor method of determining whether the repair expenditures for electric transmission and distribution property can be currently deducted for tax purposes. PPL Electric adopted the safe harbor method with the filing of its 2011 federal income tax return and recorded a $5 million adjustment to federal and state income tax expense in 2012 resulting from the reversal of prior years’ state income tax benefits related to regulated depreciation.

[14] Excludes current and deferred federal and state tax expense (benefit) recorded to Discontinued Operations of less than $1 million in 2014, $1 million in 2013,and $(4) million in 2012.Also, excludes deferred federal and state tax expense (benefit) recorded to OCI of $(36) million in 2014, $18 million in 2013and $(12) million in 2012.

[15] During 2012, LKE recorded adjustments to deferred taxes related to net operating loss carryforwards based on income tax return adjustments.

[16] Excludes deferred federal and state tax expense (benefit) recorded to OCI of less than$(1) million in both 2014 and in 2013 and $1 million in 2012.