Financing Activities (Credit Arrangements and ST Debt) (Details) In Millions, unless otherwise specified	3 Months Ended					3 Months Ended					3 Months Ended														3 Months Ended		3 Months Ended		3 Months Ended		3 Months Ended							3 Months Ended			3 Months Ended					3 Months Ended								3 Months Ended		3 Months Ended
	Mar. 31, 2012 PPL WW [Member] Syndicated Credit Facility [Member] GBP (£)		Dec. 31, 2011 PPL WW [Member] Syndicated Credit Facility [Member] GBP (£)		Mar. 31, 2012 PPL WW [Member] Syndicated Credit Facility [Member] USD Denominated Borrowing [Member] USD ($)	Mar. 31, 2012 WPD South West [Member] Syndicated Credit Facility [Member] GBP (£)		Mar. 31, 2012 WPD South West [Member] Replaced Credit Facility [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2012 WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2011 WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2012 WPD West Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2011 WPD West Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Mar. 31, 2012 WPD [Member] USD ($)		Mar. 31, 2012 WPD [Member] GBP (£)		Dec. 31, 2011 WPD [Member] GBP (£)		Mar. 31, 2012 WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Dec. 31, 2011 WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Mar. 31, 2012 PPL Energy Supply [Member] USD ($)		Dec. 31, 2011 PPL Energy Supply [Member] USD ($)		Mar. 31, 2012 PPL Energy Supply [Member] Commercial Paper [Member] USD ($)	Apr. 30, 2012 PPL Energy Supply [Member] Commercial Paper [Member] USD ($)	Mar. 31, 2012 PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2012 PPL Energy Supply [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Letter Of Credit Facility [Member] USD ($)	Mar. 31, 2012 PPL Energy Supply [Member] Facility Agreement [Member] USD ($)	Mar. 31, 2012 PPL Energy Supply [Member] Secured Trading Facility [Member] USD ($) Integer	Mar. 31, 2012 PPL Electric [Member] USD ($)		Dec. 31, 2011 PPL Electric [Member] USD ($)		Mar. 31, 2012 PPL Electric [Member] Commercial Paper [Member] USD ($)	Mar. 31, 2012 PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2011 PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2012 PPL Electric [Member] Asset Backed Credit Facility [Member] USD ($)		Dec. 31, 2011 PPL Electric [Member] Asset Backed Credit Facility [Member] USD ($)	Apr. 30, 2012 PPL Electric [Member] Subsequent To Period End Activity [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2012 LGE [Member] Commercial Paper [Member] USD ($)	Mar. 31, 2012 LGE [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2011 LGE [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2012 KU [Member] USD ($)		Dec. 31, 2011 KU [Member] USD ($)		Mar. 31, 2012 KU [Member] Commercial Paper [Member] USD ($)	Mar. 31, 2012 KU [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2011 KU [Member] Syndicated Credit Facility [Member] USD ($)	Mar. 31, 2012 KU [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2011 KU [Member] Letter Of Credit Facility [Member] USD ($)
Credit Facility [Line Items]
Expiration date	Jan. 2013					Jan. 2017		July 2012	Apr. 2016		Apr. 2016																Oct. 2016		Mar. 2013		June 2017	November 2015						Oct. 2016			July 2012					Oct. 2016								Oct. 2016		Apr. 2014
Capacity	£ 150					£ 245	[1]	£ 210	£ 300		£ 300				£ 1,068				£ 73		$ 3,200	[2]					$ 3,000		$ 200				$ 350	[2]				$ 200	[3]		$ 150	[4]		$ 300		$ 400	[2],[5]		$ 598	[2],[5]				$ 400		$ 198
Borrowed	110	[6],[7]	111	[6]	174										110	[6]	111	[6]
Letters of credit issued and commercial paper backstop									70	70	71	71			144		144		3	3	778	[2]	630	[2]			634	541	144	89			1	[2]	1	[2]		1		1						0		0	198	[2],[5]	198	[2],[5]		0	0	198	198
Unused capacity	40					245	[1]		230		229		1,300	[8]	814				70		2,422	[2]					2,366		56				349	[2]				199			150	[4]				400	[2],[5]		400	[2],[5]				400		0
Interest rate on outstanding borrowing	1.458%
Minimum interest coverage ratio allowed under the credit facility						3.0 times
Minimum percentage of RAV to total net debt allowed under the credit facility						85.00%
Accounts receivable pledged under the credit facility																																									260		251
Unbilled revenue pledged under the credit facility																																									75		98
Available capacity under the asset-backed credit facility																																									82
Potential maximum Facility Agreement capacity																															500
Secured energy marketing and trading facility capacity																																800
Automatic renewal term (in years)																																1
Short-term Debt [Line Items]
Capacity																									500	750											200								250								250
Commercial paper outstanding																									$ 500
Weighted-average interest rate on outstanding commercial paper																									0.47%

[1] In January 2012, WPD (South West) entered into a new £245 million 5-year syndicated credit facility to replace its existing £210 million 3-year syndicated credit facility that was set to expire in July 2012. Under the facility, WPD (South West) has the ability to make cash borrowings but cannot request the lenders to issue letters of credit. WPD (South West) pays customary commitment fees under this facility and borrowings bear interest at LIBOR-based rates plus a margin. The credit facility contains financial covenants that require WPD (South West) to maintain an interest coverage ratio of not less than 3.0 times consolidated earnings before income taxes, depreciation and amortization and total net debt not in excess of 85% of its RAV, in each case calculated in accordance with the credit facility.

[2] All credit facilities at PPL Energy Supply, PPL Electric, LG&E and KU also apply to PPL on a consolidated basis for financial reporting purposes.

[3] In April 2012, PPL Electric increased the capacity of its syndicated credit facility to $300 million.

[4] PPL Electric participates in an asset-backed commercial paper program through which PPL Electric obtains financing by selling and contributing its eligible accounts receivable and unbilled revenue to a special purpose, wholly owned subsidiary on an ongoing basis. The subsidiary has pledged these assets to secure loans from a commercial paper conduit sponsored by a financial institution.         At March 31, 2012 and December 31, 2011, $260 million and $251 million of accounts receivable and $75 million and $98 million of unbilled revenue were pledged by the subsidiary under the credit agreement related to PPL Electric's and the subsidiary's participation in the asset-backed commercial paper program. Based on the accounts receivable and unbilled revenue pledged at March 31, 2012, the amount available for borrowing under the facility was limited to $82 million. PPL Electric's sale to its subsidiary of the accounts receivable and unbilled revenue is an absolute sale of assets, and PPL Electric does not retain an interest in these assets. However, for financial reporting purposes, the subsidiary's financial results are consolidated in PPL Electric's financial statements. PPL Electric performs certain record-keeping and cash collection functions with respect to the assets in return for a servicing fee from the subsidiary.

[5] All credit facilities at LG&E and KU also apply to LKE on a consolidated basis for financial reporting purposes.

[6] Amounts borrowed are recorded as "Short-term debt" on the Balance Sheets.

[7] The borrowing outstanding at March 31, 2012 was a USD-denominated borrowing of $174 million, which equated to £110 million at the time of borrowing and bore interest at approximately 1.458%.

[8] At March 31, 2012, the unused capacity of the WPD credit facilities was approximately $1.3 billion.