Retirement and Postemployment Benefits (Net Period Defined Benefit Costs (Credits) and Other Changes in Plan Assets and Benefit Obligations) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		$ 96		$ 97		$ 119
Interest cost		194		224		205
Expected return on plan assets		(258)		(287)		(283)
Amortization of:
Prior service cost (credits)		7		20		22
Actuarial (gain) loss		84		28		77
Net periodic defined benefit costs (credits) prior to settlement charges, curtailment charges (credits) and termination benefits		123		82		140
Termination benefits		0		13		0
Net periodic defined benefit costs (credits)		123		95		140
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Divestiture		(353)	[1]	0		0
Net (gain) loss		63		574		(304)
Prior service costs (credit)		18		(8)		0
Amortization of: [Abstract]
Prior service (cost) credit		(7)		(20)		(22)
Actuarial gain (loss)		(85)		(28)		(77)
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities		(364)		518		(403)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities		(241)		613		(263)
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
OCI		(269)		319		(210)
Regulatory assets/liabilities		(95)		199		(193)
Total recognized in OCI and regulatory assets/liabilities		(364)		518		(403)
Estimated Amounts to be Amortized From AOCI and Regulatory Assets into Net Periodic Benefit Costs in the Next Fiscal Period (Details) [Abstract]
Prior service cost (credit)		8
Actuarial (gain) loss		49
Total		57
Amortization from Balance Sheet: [Abstract]
AOCI		12
Regulatory assets/liabilities		45
Total		57
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		$ 71		45		72
Amortization period for the deferred recovery of a regulatory asset		15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		$ 4
Pension Benefits United Kingdom [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		79		71		69
Interest cost		314		354		320
Expected return on plan assets		(523)		(521)		(465)
Amortization of:
Prior service cost (credits)		0		0		1
Actuarial (gain) loss		158		132		150
Net periodic defined benefit costs (credits) prior to settlement charges, curtailment charges (credits) and termination benefits		28		36		75
Termination benefits		0		0		3
Net periodic defined benefit costs (credits)		28		36		78
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Net (gain) loss		508		354		76
Prior service costs (credit)		0		0		0
Amortization of: [Abstract]
Prior service (cost) credit		0		0		(1)
Actuarial gain (loss)		(158)		(132)		(150)
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities	[2]	350		222		(75)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities	[2]	378		258		3
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
Total recognized in OCI and regulatory assets/liabilities	[2]	350		222		(75)
Estimated Amounts to be Amortized From AOCI and Regulatory Assets into Net Periodic Benefit Costs in the Next Fiscal Period (Details) [Abstract]
Prior service cost (credit)		0
Actuarial (gain) loss		151
Total		151
Amortization from Balance Sheet: [Abstract]
AOCI		151
Regulatory assets/liabilities		0
Total		151
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		(21)		(9)		33
Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		11		12		13
Interest cost		26		31		29
Expected return on plan assets		(26)		(26)		(25)
Amortization of:
Prior service cost (credits)		1		0		0
Actuarial (gain) loss		0		1		6
Net periodic defined benefit costs (credits) prior to settlement charges, curtailment charges (credits) and termination benefits		12		18		23
Termination benefits		0		0		0
Net periodic defined benefit costs (credits)		12		18		23
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Divestiture		(6)	[1]	0		0
Net (gain) loss		(9)		22		(67)
Prior service costs (credit)		0		7		0
Amortization of: [Abstract]
Prior service (cost) credit		(1)		0		0
Actuarial gain (loss)		0		(1)		(6)
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities		(16)		28		(73)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities		(4)		46		(50)
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
OCI		12		7		(37)
Regulatory assets/liabilities		(28)		21		(36)
Total recognized in OCI and regulatory assets/liabilities		(16)		28		(73)
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		8		10		13
PPL Electric Utilities Corp [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts	[3]	15		12		18
PPL Electric Utilities Corp [Member] | Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		0		2	[3]	3	[3]
LG And E And KU Energy LLC [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		(9)
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		26		21		26
Interest cost		68		66		62
Expected return on plan assets		(88)		(82)		(82)
Amortization of:
Prior service cost (credits)		7		5		5
Actuarial (gain) loss		37	[4]	12		33
Net periodic defined benefit costs (credits)		50		22		44
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Net (gain) loss		20		162		(116)
Prior service costs (credit)		19		23		0
Amortization of: [Abstract]
Prior service (cost) credit		(7)		(5)		(5)
Actuarial gain (loss)		(37)		(12)		(33)
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities		(5)		168		(154)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities		45		190		(110)
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
OCI		4		84		(46)
Regulatory assets/liabilities		(9)		84		(108)
Total recognized in OCI and regulatory assets/liabilities		(5)		168		(154)
Estimated Amounts to be Amortized From AOCI and Regulatory Assets into Net Periodic Benefit Costs in the Next Fiscal Period (Details) [Abstract]
Prior service cost (credit)		8
Actuarial (gain) loss		20
Total		28
Amortization from Balance Sheet: [Abstract]
AOCI		2
Regulatory assets/liabilities		26
Total		28
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		$ 37	[5]	17		32
Amortization period for the deferred recovery of a regulatory asset		15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		$ 4
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		5		4		5
Interest cost		9		9		8
Expected return on plan assets		(6)		(4)		(5)
Amortization of:
Prior service cost (credits)		3		2		3
Actuarial (gain) loss		0		(1)		0
Net periodic defined benefit costs (credits)		11		10		11
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Net (gain) loss		(15)		26		(14)
Prior service costs (credit)		0		6		0
Amortization of: [Abstract]
Prior service (cost) credit		(3)		(2)		(3)
Actuarial gain (loss)		0		1		0
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities		(18)		31		(17)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities		(7)		41		(6)
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
OCI		(2)		9		(1)
Regulatory assets/liabilities		(16)		22		(16)
Total recognized in OCI and regulatory assets/liabilities		(18)		31		(17)
Estimated Amounts to be Amortized From AOCI and Regulatory Assets into Net Periodic Benefit Costs in the Next Fiscal Period (Details) [Abstract]
Prior service cost (credit)		2
Actuarial (gain) loss		0
Total		2
Amortization from Balance Sheet: [Abstract]
AOCI		1
Regulatory assets/liabilities		1
Total		2
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		8		7		8
Louisville Gas And Electric Co [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		(3)
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits): [ Abstract]
Service cost		1		1		2
Interest cost		14		15		14
Expected return on plan assets		(20)		(19)		(20)
Amortization of:
Prior service cost (credits)		3		2		2
Actuarial (gain) loss		11	[6]	6		14
Net periodic defined benefit costs (credits)		9		5		12
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross: [Abstract]
Net (gain) loss		8		14		(20)
Prior service costs (credit)		10		9		0
Amortization of: [Abstract]
Prior service (cost) credit		(3)		(2)		(2)
Actuarial gain (loss)		(11)		(6)		(14)
Acquisition of regulatory assets/liabilities: [Abstract]
Total recognized in OCI and regulatory assets/liabilities		4		15		(36)
Total recognized in net periodic benefit costs, OCI and regulatory assets/liabilities		13		20		(24)
Other Changes in Plan Assets and Benefit Obligations Recognized in OCI and Regulatory Assets/Liabilities - Gross (Details) [Abstract]
Total recognized in OCI and regulatory assets/liabilities		4		15		(36)
Estimated Amounts to be Amortized From AOCI and Regulatory Assets into Net Periodic Benefit Costs in the Next Fiscal Period (Details) [Abstract]
Prior service cost (credit)		5
Actuarial (gain) loss		7
Total		12
Amortization from Balance Sheet: [Abstract]
Total		12
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		$ 12	[5]	5		14
Amortization period for the deferred recovery of a regulatory asset		15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		$ 4
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors		5		2		5
Louisville Gas And Electric Co [Member] | Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts		4		4		4
Louisville Gas And Electric Co [Member] | Other Postretirement Benefits United States [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors		4		4		4
Kentucky Utilities Co [Member] | Pension Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts	[3]	$ 9	[5]	3		9
Amortization period for the deferred recovery of a regulatory asset		15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period		$ 1
Kentucky Utilities Co [Member] | Other Postretirement Benefits United States [Member]
Net Periodic Defined Benefit Costs (Credits) Charged to Operating Expense or Regulatory Assets, Excluding Amounts Charged to Construction and Other Non-expense Accounts (Details) [Abstract]
Net periodic defined benefit costs (credits) charged to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts	[3]	$ 2		$ 2		$ 2

[1] As a result of the spinoff of PPL Energy Supply, amounts in AOCI were allocated to certain former active and inactive employees of PPL Energy Supply and included in the distribution . See Note 8 for additional details.

[2] WPD is not subject to accounting for the effects of certain types of regulation as prescribed by GAAP. As a result, WPD does not record regulatory assets/liabilities.

[3] PPL Electric and KU do not directly sponsor any defined benefit plans. PPL Electric and KU were allocated these costs of defined benefit plans sponsored by PPL Services (for PPL Electric) and by LKE (for KU), based on their participation in those plans, which management believes are reasonable.

[4] As a result of the 2014 Kentucky rate case settlement that became effective July 1, 2015, the difference between actuarial (gain)/loss calculated in accordance with LKE’s pension accounting policy and actuarial (gain)/loss calculated using a 15 year amortization period was $ 9 million.

[5] As a result of the 2014 Kentucky rate case settlement that became effective July 1, 2015, the difference between net periodic defined benefit costs calculated in acco rdance with LKE’s, LG&E’s and KU’s pension accounting policy and the net periodic defined benefit costs calculated using a 15 year amortization period for gains and losses is recorded as a regulatory asset. Of the costs charge d to operating expense or regulatory assets, excluding amounts charged to construction and other non-expense accounts, $ 4 million for LG&E and $ 1 million for KU were recorded as regulatory assets.

[6] As a result of the 2014 Kentucky rate case settlement that became effective July 1, 2015, the difference between actuarial (gain)/loss calculated in accordance with LG&E’s pension accounting policy and actuarial (gain)/loss calculated using a 15 year amortization period was $ 3 million.