Utility Rate Regulation (Regulatory Liabilities) (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015
Regulatory Liabilities [Line Items]
Current regulatory liabilities		$ 101	$ 145
Noncurrent regulatory liabilities		899	945
Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		23	41
Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		3	8
Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	6
Universal Service Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		14	5
Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		15	48
Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		11	14
Storm Damage Expense [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		13	16
Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		700	691
Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	0	17
Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	75	83
Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	23
Act 129 Compliance Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		17	0
Noncurrent regulatory liabilities		0	22
Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	24
Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		78	82
Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		5	7
Noncurrent regulatory liabilities		0	3
PPL Electric Utilities Corp [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		83	113
Noncurrent regulatory liabilities		0	22
PPL Electric Utilities Corp [Member] | Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		23	41
PPL Electric Utilities Corp [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Universal Service Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		14	5
PPL Electric Utilities Corp [Member] | Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		15	48
PPL Electric Utilities Corp [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Storm Damage Expense [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		13	16
PPL Electric Utilities Corp [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Act 129 Compliance Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		17	0
Noncurrent regulatory liabilities		0	22
PPL Electric Utilities Corp [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
PPL Electric Utilities Corp [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		1	3
Noncurrent regulatory liabilities		0	0
LG And E And KU Energy LLC [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		18	32
Noncurrent regulatory liabilities		899	923
LG And E And KU Energy LLC [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		3	8
LG And E And KU Energy LLC [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	6
LG And E And KU Energy LLC [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		11	14
LG And E And KU Energy LLC [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		700	691
LG And E And KU Energy LLC [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	0	17
LG And E And KU Energy LLC [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	75	83
LG And E And KU Energy LLC [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	23
LG And E And KU Energy LLC [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	24
LG And E And KU Energy LLC [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		78	82
LG And E And KU Energy LLC [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		4	4
Noncurrent regulatory liabilities		0	3
Louisville Gas And Electric Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		5	13
Noncurrent regulatory liabilities		419	431
Louisville Gas And Electric Co [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		2	4
Louisville Gas And Electric Co [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	6
Louisville Gas And Electric Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		2	2
Louisville Gas And Electric Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		305	301
Louisville Gas And Electric Co [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	0	7
Louisville Gas And Electric Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	52	57
Louisville Gas And Electric Co [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	23
Louisville Gas And Electric Co [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
Louisville Gas And Electric Co [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		39	41
Louisville Gas And Electric Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		1	1
Noncurrent regulatory liabilities		0	2
Kentucky Utilities Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		13	19
Noncurrent regulatory liabilities		480	492
Kentucky Utilities Co [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		1	4
Kentucky Utilities Co [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	0
Kentucky Utilities Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		9	12
Kentucky Utilities Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		395	390
Kentucky Utilities Co [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	0	10
Kentucky Utilities Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	23	26
Kentucky Utilities Co [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	0
Kentucky Utilities Co [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	24
Kentucky Utilities Co [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		39	41
Kentucky Utilities Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		3	3
Noncurrent regulatory liabilities		$ 0	$ 1

[1] These liabilities were recorded as offsets to certain intangible assets that were recorded at fair value upon the acquisition of LKE by PPL.