Commitments and Contingencies (Guarantees and Other Assurances) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Guarantor Obligations [Line Items]
Recorded liability for all guarantees	38		$ 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	12	[1]
Expiration date	2018
Minimum period that indemnifications generally expire (in years)	2
Maximum period that indemnifications generally expire (in years)	7
PPL Guarantee [Member] | Financial Guarantee [Member] | WPD Guarantee Of Pension And Other Obligations Of Unconsolidated Entities [Member]
Guarantor Obligations [Line Items]
Maximum exposure	119	[2]
PPL Energy Supply Guarantee [Member] | Indemnification Guarantee [Member] | Indemnifications For Sales Of Assets [Member]
Guarantor Obligations [Line Items]
Maximum exposure	1,150	[3]
Expiration date minimum	2016
Expiration date maximum	2025
PPL Electric Guarantee [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	34	[4]
Expiration date	2017
LKE Guarantee [Member] | Indemnification Guarantee [Member] | Indemnification Of Lease Termination And Other Divestitures [Member]
Guarantor Obligations [Line Items]
Maximum exposure	301	[5]
Expiration date minimum	2021
Expiration date maximum	2023
Term of guarantee (in years)	12
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues	200
Maximum exposure of other guarantees expiring related to a terminated lease	100
Charge recorded in discontinued operations relating to certain indemnification, pre-tax	9
Charge recorded in discontinued operations relating to certain indemnification, after-tax	5
LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Contingent potential proportionate share of OVEC's outstanding debt	125
PPL Energy Supply LLC [Member]
Guarantor Obligations [Line Items]
Recorded liability for all guarantees	13
PPL Energy Supply LLC [Member] | Indemnification Guarantee [Member] | Indemnifications For Sales Of Assets [Member]
Guarantor Obligations [Line Items]
Maximum exposure	1,150	[3]
Expiration date minimum	2016
Expiration date maximum	2025
PPL Energy Supply LLC [Member] | Financial Guarantee [Member] | Letters Of Credit Issued On Behalf Of Affiliates [Member]
Guarantor Obligations [Line Items]
Maximum exposure	25	[6]
Expiration date minimum	2015
Expiration date maximum	2016
PPL Electric Utilities Corp [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	34	[4]
Expiration date	2017
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	301	[5]
Expiration date minimum	2021
Expiration date maximum	2023
Term of guarantee (in years)	12
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues	200
Maximum exposure of other guarantees expiring related to a terminated lease	100
Charge recorded in discontinued operations relating to certain indemnification, pre-tax	9
Charge recorded in discontinued operations relating to certain indemnification, after-tax	5
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. See "Energy Purchase Commitments" above for additional information on the OVEC power purchase contract.
Contingent potential proportionate share of OVEC's outstanding debt	125
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. See "Energy Purchase Commitments" above for additional information on the OVEC power purchase contract.
Louisville Gas And Electric Co [Member] | LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Contingent potential proportionate share of OVEC's outstanding debt	87
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. See "Energy Purchase Commitments" above for additional information on the OVEC power purchase contract.
Kentucky Utilities Co [Member] | LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Contingent potential proportionate share of OVEC's outstanding debt	38

[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 agreements 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 December 31, 2014, WPD has recorded an estimated discounted 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 been estimated.

[3] Indemnifications are governed by the specific sales agreement and include breach of the representations, warranties and covenants, and liabilities for certain other matters. PPL Energy Supply's maximum exposure with respect to certain indemnifications and the expiration of the indemnifications cannot be estimated because the maximum potential liability is not capped by the transaction documents and the expiration date is based on the applicable statute of limitations. The exposure and expiration date noted is based on those cases in which the agreements provide for specific limits.The exposure at December 31, 2014 includes amounts related to the sale of the Montana Hydroelectric facilities. See Note 8 for additional information related to the sale.

[4] 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 remaining inventory that has not been used or sold.

[5] LKE provides certain indemnifications, the most significant of which relate to the termination of the WKE lease in July 2009.These guarantees cover the due and punctual payment, performance and discharge by each party of its respective present and future obligations. The most comprehensive of these WKE-related guarantees is the LKE guarantee covering operational, regulatory and environmental commitments and indemnifications made by WKE under the WKE Transaction Termination Agreement. This guarantee has a term of 12 years ending July 2021, and a cumulative maximum exposure of $200 million. Certain items such as government fines and penalties fall outside the cumulative cap.Another WKE-related LKE guarantee covers other indemnifications, has 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, which granted LKE’s indemnitee certain rights of first refusal to purchase excess power at a market-based price rather than at an absolute fixed price. In January 2013, LKE's indemnitee commenced a proceeding in the Kentucky Court of Appeals appealing a December 2012 order of the Henderson Circuit Court, confirming the arbitration award.In May 2014, the Court of Appeals issued an opinion affirming the lower court decision. LKE's indemnitee filed a Motion for Discretionary Review with the Kentucky Supreme Court on October 2, 2014.LKE believes its indemnification obligations in this matter remain subject to various uncertainties, including potential for additional legal challenges regarding the arbitration decision as well as future prices, availability and demand for the subject excess power. LKE continues to evaluate various legal and commercial options with respect to this indemnification matter. The ultimate outcomes of the WKE termination-related indemnifications cannot be predicted at this time. In the second quarter of 2012, LKE adjusted its estimated liability for the WKE-related indemnifications by $9 million ($5 million after-tax), which is reflected in "Income (Loss) from Discontinued Operations (net of income taxes)" on the Statement of Income. The adjustment was recorded in the Kentucky Regulated segment for PPL. Additionally, LKE has indemnified 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. However, LKE is not aware of formal claims under such indemnities made by any party at this time. LKE cannot predict the ultimate outcomes of indemnification circumstances, but does not currently expect such outcomes to result in significant losses above the amounts recorded.

[6] Standby letter of credit arrangements under PPL Energy Supply's credit facilities for the purposes of protecting various third parties against nonperformance by PPL. This is not a guarantee by PPL on a consolidated basis.