Retirement and Postemployment Benefits (Weighted-Average Assumptions, Cost Trend Rates and Funded Status) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent liabilities of discontinued operations		$ 0		$ (3,953)
Pension Benefits United States [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		4.59%		4.25%
Benefit obligations valuation rate of compensation increase		3.93%		3.91%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		4.25%		5.12%		4.22%
Net periodic benefit costs rate of compensation increase		3.91%		3.97%		3.98%
Net periodic benefit costs expected return on plan assets	[1]	7.00%		7.00%		7.03%
Assumed Health Care Cost Trend Rates (Details) [Abstract]
Health care cost trend rate assumed for next year, obligations		6.80%		7.20%		7.60%
Health care cost trend rate assumed for next year, cost		7.20%		7.60%		8.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate), obligations		5.00%		5.00%		5.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate),cost		5.00%		5.00%		5.50%
Year that the rate reaches the ultimate trend rate, obligations		2020		2020		2020
Year that the rate reaches the ultimate trend rate, cost		2020		2020		2019
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		$ 5,399		$ 4,428
Service cost		96		97		$ 119
Interest cost		194		224		205
Participant contributions		0		0
Plan amendments		19		(7)
Actuarial (gain) loss		(193)		887
Divestiture		(1,416)	[2]	0
Termination benefits		0		13
Gross benefits paid		(236)		(243)	[3]
Currency conversion		0		0
Benefit Obligation, end of period		3,863		5,399		4,428
Change in Plan Assets [Roll Forward]
Balance at beginning of period		4,462		4,009
Actual return on plan assets		2		600
Employer contributions		158		96
Participant contributions		0		0
Divestiture		(1,159)	[2]	0
Gross benefits paid		(236)		(243)	[3]
Currency conversion		0		0
Balance at end of period		3,227		4,462		$ 4,009
Funded Status, end of period		(636)		(937)
Lump sum cash payouts made to terminated vested employees		33
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent asset		0		0
Current liability		(10)		(10)
Noncurrent liability		(626)		(668)
Noncurrent liabilities of discontinued operations		0		(259)
Net amount recognized, end of period		(636)		(937)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		53		41
Net actuarial (gain) loss		977		1,353
Total		1,030		1,394
Total accumulated benefit obligation for defined benefit pension plans		3,590		4,946
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
AOCI		275		714
Regulatory assets/liabilities		755		680
Total		1,030		1,394
Pension Plans Where the Projected or Accumulated Benefit Obligation Exceed the Value of Plan Assets (Details) [Abstract]
Projected benefit obligations		3,863		5,399
Fair value of plan assets where the projected benefit obligations exceed the value of plan assets		3,227		4,462
Accumulated benefit obligation		3,590		4,946
Fair value of plan assets where the accumulated benefit obligations exceed the value of plan assets		$ 3,227		$ 4,462
Pension Benefits United Kingdom [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		3.68%		3.85%
Benefit obligations valuation rate of compensation increase		4.00%		4.00%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		3.85%		4.41%		4.27%
Net periodic benefit costs rate of compensation increase		4.00%		4.00%		4.00%
Net periodic benefit costs expected return on plan assets	[1]	7.19%		7.19%		7.16%
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		$ 8,523		$ 8,143
Service cost		79		71		$ 69
Interest cost		314		354		320
Participant contributions		15		16
Plan amendments		0		0
Actuarial (gain) loss		200		747
Divestiture		0		0
Termination benefits		0		0
Gross benefits paid		(391)		(411)
Currency conversion		(336)		(397)
Benefit Obligation, end of period		8,404		8,523		8,143
Change in Plan Assets [Roll Forward]
Balance at beginning of period		7,734		7,284
Actual return on plan assets		205		895
Employer contributions		366		311
Participant contributions		15		16
Divestiture		0		0
Gross benefits paid		(391)		(411)
Currency conversion		(304)		(361)
Balance at end of period		7,625		7,734		$ 7,284
Funded Status, end of period		(779)		(789)
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent asset		0		0
Current liability		0		(1)
Noncurrent liability		(779)		(788)
Net amount recognized, end of period		(779)		(789)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		0		0
Net actuarial (gain) loss		2,684		2,334
Total	[4]	2,684		2,334
Total accumulated benefit obligation for defined benefit pension plans		7,747		7,867
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
Total	[4]	2,684		2,334
Pension Plans Where the Projected or Accumulated Benefit Obligation Exceed the Value of Plan Assets (Details) [Abstract]
Projected benefit obligations		8,404		8,523
Fair value of plan assets where the projected benefit obligations exceed the value of plan assets		7,625		7,734
Accumulated benefit obligation		3,532		3,592
Fair value of plan assets where the accumulated benefit obligations exceed the value of plan assets		$ 3,287		$ 3,321
Other Postretirement Benefits United States [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		4.48%		4.09%
Benefit obligations valuation rate of compensation increase		3.91%		3.86%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		4.09%		4.91%		4.00%
Net periodic benefit costs rate of compensation increase		3.86%		3.96%		3.97%
Net periodic benefit costs expected return on plan assets	[1]	6.06%		5.96%		5.94%
Effect of One Percentage Point Change in Assumed Health Care Costs Trend Rate (Details) [Abstract]
Effect on accumulated postretirement benefit obligation of a one percentage point increase		$ 6
Effect on accumulated postretirement benefit obligation of a one percentage point decrease		(5)
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		716		$ 650
Service cost		11		12		$ 13
Interest cost		26		31		29
Participant contributions		13		12
Plan amendments		0		6
Actuarial (gain) loss		(37)		59
Divestiture		(76)	[2]	0
Termination benefits		0		0
Gross benefits paid		(58)		(55)
Federal subsidy		1		1
Currency conversion		0		0
Benefit Obligation, end of period		596		716		650
Change in Plan Assets [Roll Forward]
Balance at beginning of period		484		446
Actual return on plan assets		(2)		62
Employer contributions		17		15
Participant contributions		13		12
Divestiture		(80)	[2]	0
Gross benefits paid		(53)		(51)
Currency conversion		0		0
Balance at end of period		379		484		$ 446
Funded Status, end of period		(217)		(232)
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent asset		2		1
Current liability		(3)		(3)
Noncurrent liability		(216)		(196)
Noncurrent liabilities of discontinued operations		0		(34)
Net amount recognized, end of period		(217)		(232)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		1		0
Net actuarial (gain) loss		37		54
Total		38		54
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
AOCI		18		30
Regulatory assets/liabilities		20		24
Total		38		54
PPL Electric Utilities Corp [Member]
Change in Plan Assets [Roll Forward]
Non-cash contributions related to remeasurement and separation of benefit plans		56
PPL Electric Utilities Corp [Member] | Pension Benefits United States [Member] | PPL Services Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		183		212
PPL Electric Utilities Corp [Member] | Other Postretirement Benefits United States [Member] | PPL Services Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		$ 67		$ 40
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		4.56%		4.25%
Benefit obligations valuation rate of compensation increase		3.50%		3.50%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		4.25%		5.18%		4.24%
Net periodic benefit costs rate of compensation increase		3.50%		4.00%		4.00%
Net periodic benefit costs expected return on plan assets	[1]	7.00%		7.00%		7.10%
Assumed Health Care Cost Trend Rates (Details) [Abstract]
Health care cost trend rate assumed for next year, obligations		6.80%		7.20%		7.60%
Health care cost trend rate assumed for next year, cost		7.20%		7.60%		8.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate), obligations		5.00%		5.00%		5.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate),cost		5.00%		5.00%		5.50%
Year that the rate reaches the ultimate trend rate, obligations		2020		2020		2020
Year that the rate reaches the ultimate trend rate, cost		2020		2020		2019
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		$ 1,608		$ 1,328
Service cost		26		21		$ 26
Interest cost		68		66		62
Participant contributions		0		0
Plan amendments	[5]	19		23
Actuarial (gain) loss		(74)		253
Gross benefits paid		(59)		(83)	[6]
Benefit Obligation, end of period		1,588		1,608		1,328
Change in Plan Assets [Roll Forward]
Balance at beginning of period		1,301		1,173
Actual return on plan assets		(7)		173
Employer contributions		54		38
Participant contributions		0		0
Gross benefits paid		(59)		(83)	[6]
Balance at end of period		1,289		1,301		$ 1,173
Funded Status, end of period		(299)		(307)
Lump sum cash payouts made to terminated vested employees				33
Increase during the period resulting from a plan amendment		19		23
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent asset		0		0
Current liability		(3)		(3)
Noncurrent liability		(296)		(304)
Net amount recognized, end of period		(299)		(307)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		54		43
Net actuarial (gain) loss		338		354
Total		392		397
Total accumulated benefit obligation for defined benefit pension plans		1,452		1,461
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
AOCI		70		65
Regulatory assets/liabilities		322		332
Total		392		397
Pension Plans Where the Projected or Accumulated Benefit Obligation Exceed the Value of Plan Assets (Details) [Abstract]
Projected benefit obligations		1,588		1,608
Fair value of plan assets where the projected benefit obligations exceed the value of plan assets		1,289		1,301
Accumulated benefit obligation		1,452		1,461
Fair value of plan assets where the accumulated benefit obligations exceed the value of plan assets		$ 1,289		$ 1,301
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		4.49%		4.06%
Benefit obligations valuation rate of compensation increase		3.50%		3.50%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		4.06%		4.91%		3.99%
Net periodic benefit costs rate of compensation increase		3.50%		4.00%		4.00%
Net periodic benefit costs expected return on plan assets	[1]	6.82%		6.75%		6.76%
Effect of One Percentage Point Change in Assumed Health Care Costs Trend Rate (Details) [Abstract]
Effect on accumulated postretirement benefit obligation of a one percentage point increase		$ 5
Effect on accumulated postretirement benefit obligation of a one percentage point decrease		(4)
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		234		$ 193
Service cost		5		4		$ 5
Interest cost		9		9		8
Participant contributions		7		7
Plan amendments		0		6
Actuarial (gain) loss		(22)		32
Gross benefits paid		(18)		(17)
Benefit Obligation, end of period		216		234		193
Change in Plan Assets [Roll Forward]
Balance at beginning of period		82		74
Actual return on plan assets		0		10
Employer contributions		17		8
Participant contributions		7		7
Gross benefits paid		(18)		(17)
Balance at end of period		88		82		$ 74
Funded Status, end of period		(128)		(152)
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent asset		2		2
Current liability		(3)		(3)
Noncurrent liability		(127)		(151)
Net amount recognized, end of period		(128)		(152)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		9		12
Net actuarial (gain) loss		(19)		(4)
Total		(10)		8
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
AOCI		7		8
Regulatory assets/liabilities		(17)		0
Total		$ (10)		$ 8
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member]
Weighted Average Assumptions Used in the Valuation of the Benefit Obligations (Details) [Abstract]
Benefit obligations valuation discount rate		4.49%		4.20%
Weighted Average Assumptions Used to Determine the Net Periodic Benefit Costs (Details) [Abstract]
Net periodic benefit costs discount rate		4.20%		5.13%		4.20%
Net periodic benefit costs expected return on plan assets	[1]	7.00%		7.00%		7.10%
Change in Benefit Obligation [Roll Forward]
Benefit Obligation, beginning of period		$ 331		$ 291
Service cost		1		1		$ 2
Interest cost		14		15		14
Plan amendments		10	[7]	9
Actuarial (gain) loss		(15)		36
Gross benefits paid		(15)	[8]	(21)
Benefit Obligation, end of period		326		331		291
Change in Plan Assets [Roll Forward]
Balance at beginning of period		301		281
Actual return on plan assets		(2)		41
Employer contributions		13		0
Gross benefits paid		(15)		(21)	[8]
Balance at end of period		297		301		$ 281
Funded Status, end of period		(29)		(30)
Lump sum cash payouts made to terminated vested employees				8
Increase during the period resulting from a plan amendment		10		9
Amounts recognized in the Balance Sheets consist of: [Abstract]
Noncurrent liability		(29)		(30)
Net amount recognized, end of period		(29)		(30)
Amounts recognized in AOCI and regulatory asets/liabilities (pre-tax): [Abstract]
Prior service cost (credit)		29		22
Net actuarial (gain) loss		95		98
Total		124		120
Total accumulated benefit obligation for defined benefit pension plans		326		330
Changes in Plan Assets and Benefit Obligations Recognized in AOCI and Regulatory Assets/Liabilities by Type (Details) [Abstract]
Total		124		120
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | LKE Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		26		27
Louisville Gas And Electric Co [Member] | Other Postretirement Benefits United States [Member] | LKE Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		77		85
Kentucky Utilities Co [Member] | Pension Benefits United States [Member] | LKE Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		46		59
Kentucky Utilities Co [Member] | Other Postretirement Benefits United States [Member] | LKE Funded Status Allocation [Member]
Change in Plan Assets [Roll Forward]
Funded Status, end of period		$ 42		$ 52

[1] The expected long-term rates of return for pension and other postretirement benefits are based on management's projections using a best-estimate of expected returns, volatilities and correlations for each asset class. Each plan's specific current and expected asset allocations are also considered in developing a reasonable return assumption.

[2] As a result of the spinoff of PPL Energy Supply, obligations and assets attributable to certain former active and inactive employees of PPL Energy Supply were transferred to Talen Energy plans.

[3] Certain U.S. pension plans offered a limited-time program in 2014 during which terminated vested participants could elect to receive their accrued pension benefit as a one-time lump sum payment. G ross benefits paid i ncludes $33 million of lump-sum cash pa yments made to terminated vested participants in 2014 in connection with these offerings.

[4] WPD is not subject to accounting for the effects of certain types of regulation as prescribed by GAAP and a s a result, does not record regulatory assets/lia bilities .

[5] The pension plans were amended in December 2015 allowing terminated vested participants to elect to receive their accrued pension benefit as a one-time lump-sum payment effective January 1, 2016. The projected benefit obligation increased by $ 19 million as a result of the amendment. The plans were amended in December 2014 to enhance the early retirement factors for all plan participants retiring on or after January 1, 2015. These modifications resulted in an increase o f $ 23 million in the plans’ projected benefit obligations as of December 31, 2014.

[6] Certain LKE pension plans offered a limited-time program in 2014 during which terminated vested participants could elect to receive thei r accrued pension benefit as a one-time lump-sum payment. The gross benefits paid includes $ 33 million of lump-sum cash payments made to terminated vested participants during 2014 in connection with these offerings.

[7] The plan was amended in December 2015 allowing terminated vested participants to elect to receive their accrued pension benefit as a one-time lump-sum payment effective January 1, 2016. The projected benefit obligation increased by $ 10 million as a result of the amendment. The plan was amended in December 2014 to enhance the early retirement factors for all plan participants retirin g on or after January 1, 2015. Th e projected benefit obligation increased by $ 9 million as a result of the amendment.

[8] LG&E's pension plan offered a limited-time program in 2014 during which terminated vested participants could elect to receive their accrued pension benefit as a one-time lump-sum payment. The gross benefits paid includes $ 8 million of lump-sum cash payments made to terminated vested participants in 2014 in connection with this offering.