Utility Rate Regulation (Regulatory Liabilities) (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Regulatory Liabilities [Line Items]
Current regulatory liabilities		$ 145	$ 91
Noncurrent regulatory liabilities		945	992
Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		41	28
Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		8	2
Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		6	6
Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		48	42
Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		14	0
Storm Damage Expense [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		16	3
Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		691	693
Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	17	59
Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	83	92
Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	26
Act 129 Compliance Rider [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		22	18
Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		24	16
Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		82	84
Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		12	10
Noncurrent regulatory liabilities		3	4
PPL Electric Utilities Corp [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		113	76
Noncurrent regulatory liabilities		22	18
PPL Electric Utilities Corp [Member] | Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		41	28
PPL Electric Utilities Corp [Member] | Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		48	42
PPL Electric Utilities Corp [Member] | Storm Damage Expense [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		16	3
PPL Electric Utilities Corp [Member] | Act 129 Compliance Rider [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		22	18
PPL Electric Utilities Corp [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		8	3
LG And E And KU Energy LLC [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		32	15
Noncurrent regulatory liabilities		923	974
LG And E And KU Energy LLC [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		8	2
LG And E And KU Energy LLC [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		6	6
LG And E And KU Energy LLC [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		14	0
LG And E And KU Energy LLC [Member] | Gas Line Tracker [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	3
LG And E And KU Energy LLC [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		691	693
LG And E And KU Energy LLC [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	17	59
LG And E And KU Energy LLC [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	83	92
LG And E And KU Energy LLC [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	26
LG And E And KU Energy LLC [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		24	16
LG And E And KU Energy LLC [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		82	84
LG And E And KU Energy LLC [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		4	4
Noncurrent regulatory liabilities		3	4
Louisville Gas And Electric Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		13	10
Noncurrent regulatory liabilities		431	458
Louisville Gas And Electric Co [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		4	1
Louisville Gas And Electric Co [Member] | Gas Supply Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		6	6
Louisville Gas And Electric Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		2	0
Louisville Gas And Electric Co [Member] | Gas Line Tracker [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		0	3
Louisville Gas And Electric Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		301	302
Louisville Gas And Electric Co [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	7	25
Louisville Gas And Electric Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	57	63
Louisville Gas And Electric Co [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		23	24
Louisville Gas And Electric Co [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		41	42
Louisville Gas And Electric Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		1	0
Noncurrent regulatory liabilities		2	2
Kentucky Utilities Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		19	5
Noncurrent regulatory liabilities		492	516
Kentucky Utilities Co [Member] | Demand Side Management [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		4	1
Kentucky Utilities Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		12	0
Kentucky Utilities Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		390	391
Kentucky Utilities Co [Member] | Coal Contracts [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	10	34
Kentucky Utilities Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	[1]	26	29
Kentucky Utilities Co [Member] | Net Deferred Tax Assets [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		0	2
Kentucky Utilities Co [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		24	16
Kentucky Utilities Co [Member] | Interest Rate Swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities		41	42
Kentucky Utilities Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities		3	4
Noncurrent regulatory liabilities		$ 1	$ 2

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