Commitments and Contingencies (Guarantees and Other Assurances) (Details) $ in Millions		9 Months Ended
		Sep. 30, 2015 USD ($) Integer	Dec. 31, 2014 USD ($)
Guarantor Obligations [Line Items]
Recorded liability for all guarantees		$ 24	$ 26
Other Guarantee (Numeric) [Abstract]
Maximum aggregate coverage bodily injury and property damage		$ 225
PPL Guarantee [Member] | Indemnification Guarantee [Member] | Indemnifications Related To WPD Midlands Acquisition [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimateable		The maximum exposure and expiration of these indemnifications cannot be estimated because the maximum potential liability is not capped and the expiration date is not specified in the transaction documents.
PPL Guarantee [Member] | Indemnification Guarantee [Member] | Indemnifications For Entities In Liquidation Sales Of Assets [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[1]	$ 11
Expiration date		2018
Minimum period that indemnifications generally expire (in years) | Integer		2
Maximum period that indemnifications generally expire (in years) | Integer		7
PPL Guarantee [Member] | Financial Guarantee [Member] | WPD Guarantee Of Pension And Other Obligations Of Unconsolidated Entities [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[2]	$ 116
PPL Electric Guarantee [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[3]	$ 36
Expiration date		2018
LKE Guarantee [Member] | Indemnification Guarantee [Member] | Indemnification Of Lease Termination And Other Divestitures [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[4]	$ 301
Expiration date minimum		2021
Expiration date maximum		2023
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues		$ 200
Term of guarantee (in years)		12
Maximum exposure of other guarantees expiring related to a terminated lease		$ 100
PPL Electric Utilities Corp [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[3]	$ 36
Expiration date		2018
LG And E And KU Energy LLC [Member]
Guarantor Obligations [Line Items]
Recorded liability for all guarantees		$ 19	$ 19
LG And E And KU Energy LLC [Member] | Indemnification Guarantee [Member] | Indemnification Of Lease Termination And Other Divestitures [Member]
Guarantor Obligations [Line Items]
Maximum exposure	[4]	$ 301
Expiration date minimum		2021
Expiration date maximum		2023
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues		$ 200
Term of guarantee (in years)		12
Maximum exposure of other guarantees expiring related to a terminated lease		$ 100
LG And E And KU Energy LLC [Member] | LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimateable		The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Louisville Gas And Electric Co [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimateable		The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Kentucky Utilities Co [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimateable		The maximum exposure and the expiration date of these potential obligations are not presently determinable.

[1] Indemnification to the liquidators and certain others for existing liabilities or expenses or liabilities arising during the liquidation process. The indemnifications are limited to distributions made from the subsidiary to its parent either prior or subsequent to liquidation or are not explicitly stated in the agreements. The indemnifications generally expire two to seven years subsequent to the date of dissolution of the entities. The exposure noted only includes those cases where the agre ements provide for specific limits. In connection with their sales of various businesses, WPD and its affiliates have provided the purchasers with indemnifications that are standard for such transactions, including indemnifications for certain pre- existing liabilities and environmental and tax matters or have agreed to continue their obligations under existing third-party guarantees, either for a set period of time following the transactions or upon the condition that the purchasers make reasonable efforts to terminate the guarantees. Finally, WPD and its affiliates remain secondarily responsible for lease payments under certain leases that they have assigned to third parties.

[2] Relates to certain obligations of discontinued or modified electric associations that were guaranteed at the time of privatization by the participating members. Costs are allocated to the members and can be reallocated if an existing member becomes insolvent. At September 30, 2015 , WPD has recorded an estimated disc ounted liability for which the expected payment/performance is probable. Neither the expiration date nor the maximum amount of potential payments for certain obligations is explicitly stated in the related agreements, and as a result, the exposure has bee n estimated.

[3] A third party logistics firm provides inventory procurement and fulfillment services. The logistics firm has title to the inventory, however, upon termination of the contracts, PPL Electric has guaranteed to purchase any remainin g inventory that has not been used or sold.

[4] LKE provides certain indemnifications covering the due and punctual payment, performance and discharge by each party of its respective obligations. The most comprehensive of these guarantees is the LK E guarantee covering operational, regulatory and environmental commitments and indemnifications made by WKE under a 2009 Transaction Termination Agreement. This guarantee has a term of 12 years ending July 2021, and a maximum expos ure of $ 200 million, exclusive of certain items such as government fines and penalties that fall outside the cap. Another WKE-related LKE guarantee covers other indemnifications related to the purchase price of excess power, h as a term expiring in 2023, and a maximum exposure of $ 100 million. In May 2012, LKE's indemnitee received an unfavorable arbitration panel's decision interpreting this matter. In October 2014, LKE’s indemnitee filed a motio n for discretionary review with the Kentucky Supreme Court seeking to overturn the arbitration decision, and such motion was denied by the court in September 2015. I n September 2015, a counterparty issued a demand letter to LKE’s indemnitee .  LKE does not believe appropriate contractual, legal or commercial grounds exist for the claim made and anticipates the indemnitee to dispute the deman d. LKE believes its indemnification obligations in the WKE matter remain subject to various uncertainties, including a dditional legal and contractual developments, as well as future prices, availability and demand for the subject excess power. The ultimate outcomes of the WKE termination-related indemnifications cannot be predicted at this time. Additionally, LKE has in demnified various third parties related to historical obligations for other divested subsidiaries and affiliates. The indemnifications vary by entity and the maximum exposures range from being capped at the sale price to no specified maximum; LKE could be required to perform on these indemnifications in the event of covered losses or liabilities being claimed by an indemnified party. LKE cannot predict the ultimate outcomes of the indemnification circumstances, but does not currently expect such outcomes to result in significant losses above the amounts recorded.