Financing Activities (Credit Arrangements and ST Debt) (Details)	12 Months Ended		12 Months Ended						12 Months Ended			1 Months Ended			12 Months Ended		1 Months Ended	12 Months Ended										12 Months Ended							12 Months Ended						12 Months Ended		12 Months Ended			12 Months Ended		1 Months Ended						12 Months Ended								12 Months Ended										12 Months Ended				12 Months Ended			12 Months Ended		1 Months Ended		12 Months Ended
	Dec. 31, 2011 Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] USD ($)	Mar. 31, 2011 Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] GBP (£)	Dec. 31, 2011 PPL WW [Member] Syndicated Credit Facility [Member] GBP (£)		Dec. 31, 2010 PPL WW [Member] Syndicated Credit Facility [Member] GBP (£)		Dec. 31, 2011 PPL WW [Member] Syndicated Credit Facility [Member] USD Denominated Borrowing [Member] USD ($)	Dec. 31, 2010 PPL WW [Member] Syndicated Credit Facility [Member] USD Denominated Borrowing [Member] USD ($)	Dec. 31, 2011 WPD South West [Member] Syndicated Credit Facility [Member] GBP (£)		Dec. 31, 2010 WPD South West [Member] Syndicated Credit Facility [Member] GBP (£)	Jan. 31, 2012 WPD South West [Member] New Facility Subsequent To Period End [Member] Syndicated Credit Facility [Member] GBP (£)	Apr. 30, 2011 WPD East Midlands And WPD West Midlands [Member] Syndicated Credit Facility [Member] USD ($)	Apr. 30, 2011 WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2011 WPD East Midlands [Member] Syndicated Credit Facility [Member] GBP (£)		Apr. 30, 2011 WPD West Midlands [Member] Syndicated Credit Facility [Member] GBP (£)	Dec. 31, 2011 WPD West Midlands [Member] Syndicated Credit Facility [Member] GBP (£)		Dec. 31, 2011 WPD [Member] USD ($)		Dec. 31, 2011 WPD [Member] GBP (£)		Dec. 31, 2010 WPD [Member] USD ($)		Dec. 31, 2010 WPD [Member] GBP (£)		Dec. 31, 2011 WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Dec. 31, 2010 WPD [Member] Uncommitted Credit Facilities [Member] GBP (£)	Dec. 31, 2010 WPD [Member] Uncommitted Credit Facilities [Member] GBP Denominated Borrowing [Member] GBP (£)	Dec. 31, 2011 PPL Energy Supply [Member] USD ($)		Dec. 31, 2010 PPL Energy Supply [Member] USD ($)		Dec. 31, 2011 PPL Energy Supply [Member] Commercial Paper [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2010 PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)		Oct. 31, 2010 PPL Energy Supply [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2010 PPL Energy Supply [Member] Letter Of Credit Facility [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Structured Credit Facility [Member]	Dec. 31, 2010 PPL Energy Supply [Member] Structured Credit Facility [Member] USD ($)		Dec. 31, 2011 PPL Energy Supply [Member] Facility Agreement [Member] USD ($)	Dec. 31, 2011 PPL Energy Supply [Member] Secured Trading Facility [Member] USD ($)	Mar. 31, 2011 PPL Energy Supply [Member] Expired Facility [Member] Structured Credit Facility [Member] USD ($)	Dec. 31, 2011 PPL Electric [Member] USD ($)		Dec. 31, 2010 PPL Electric [Member] USD ($)		Dec. 31, 2011 PPL Electric [Member] Commercial Paper [Member] USD ($)	Dec. 31, 2011 PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2010 PPL Electric [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2011 PPL Electric [Member] Asset Backed Credit Facility [Member] USD ($)		Dec. 31, 2010 PPL Electric [Member] Asset Backed Credit Facility [Member] USD ($)	Feb. 28, 2012 LGE [Member] Short Term Debt Activity Subsequent To Period End [Member] Commercial Paper [Member] USD ($)	Dec. 31, 2011 LGE [Member] Syndicated Credit Facility [Member] USD ($)		Jun. 30, 2011 LGE [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2010 LGE [Member] Syndicated Credit Facility [Member] USD ($)		Dec. 31, 2011 KU [Member] USD ($)		Dec. 31, 2010 KU [Member] USD ($)		Feb. 28, 2012 KU [Member] Short Term Debt Activity Subsequent To Period End [Member] Commercial Paper [Member] USD ($)	Dec. 31, 2011 KU [Member] Syndicated Credit Facility [Member] USD ($)		Jun. 30, 2011 KU [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2010 KU [Member] Syndicated Credit Facility [Member] USD ($)	Dec. 31, 2011 KU [Member] Letter Of Credit Facility [Member] USD ($)		Apr. 30, 2011 KU [Member] Letter Of Credit Facility [Member]	Dec. 31, 2011 PPL Capital Funding [Member] Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] USD ($)	Dec. 31, 2011 PPL Capital Funding [Member] Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] GBP (£)	May 31, 2011 PPL WEM [Member] Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] GBP (£)	Apr. 30, 2011 PPL WEM [Member] Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] GBP (£)	Dec. 31, 2011 PPL WEM [Member] Expired Short Term Debt Facility [Member] Bridge Loan 2011 [Member] GBP (£)
Credit Arrangements Details [Abstract]
Expiration date			Jan. 2013						July 2012						Apr. 2016			Apr. 2016																		Oct. 2016					Mar. 2013		Mar. 2011			June 2017	November 2015	March 2011						Oct. 2016				July 2012				Oct. 2016										Oct. 2016				Apr. 2014
Capacity			£ 150,000,000	[1]					£ 210,000,000	[2]		£ 245,000,000			£ 300,000,000	[3]		£ 300,000,000	[3]			£ 1,033,000,000	[4]					£ 73,000,000			$ 3,200,000,000	[5]				$ 3,000,000,000	[6],[7]				$ 200,000,000						$ 800,000,000	$ 300,000,000	$ 350,000,000	[5]				$ 200,000,000	[6],[8]			$ 150,000,000	[9]			$ 400,000,000	[10],[11],[5],[6]				$ 598,000,000	[10],[5]				$ 400,000,000	[11],[6]			$ 198,000,000	[12]
Borrowed			111,000,000	[1],[13]	115,000,000	[1],[13]	178,000,000	181,000,000	0		0				0			0		178,000,000	[13],[4]	111,000,000		181,000,000	[13],[4]	115,000,000		0		0	0		350,000,000	[13],[5]		0		350,000,000	[13],[7]	3,200,000,000									0		0			0		0		0		0		0			163,000,000	[10],[13],[14],[5]	0		0			0			0
Letters of credit issued															70,000,000	[3]		71,000,000	[3]			144,000,000	[4]			3,000,000	[4]	3,000,000	3,000,000		630,000,000	[5]	185,000,000	[5]		541,000,000	[6],[7]	0			89,000,000	24,000,000		161,000,000	[15]				1,000,000	[5]	13,000,000	[5]		1,000,000	[6],[8]	13,000,000	[8]					0			0		198,000,000	[10],[5]	198,000,000	[10],[5]		0			198,000,000	198,000,000	[12]
Unused capacity			39,000,000	[1]					210,000,000	[2]					230,000,000	[3]		229,000,000	[3]	1,200,000,000	[4]	778,000,000						70,000,000			2,570,000,000	[5]				2,459,000,000	[6],[7]				111,000,000								349,000,000	[5]				199,000,000	[6],[8]			150,000,000	[9]			400,000,000	[10],[11],[5],[6]				400,000,000	[10],[5]				400,000,000	[11],[6]			0
Interest rate on outstanding borrowing			1.05%		0.94%																																			2.26%																									2.27%
Minimum interest coverage ratio allowed under the credit facility			not less than 3.0						not less than 3.0			not less than 3.0		not less than 3.0			not less than 3.0
Minimum percentage of RAB to total net debt allowed under the credit facility			15.00%
Minimum amount of RAB to total net debt allowed under the credit facility			150,000,000
Maximum percentage of total net debt to RAB allowed under the credit facility									85.00%			85.00%		85.00%			85.00%
Origination date												January 2012		April 2011			April 2011
Maximum amount of letters of credit that may be issued under credit facility														80,000,000			80,000,000
Weighted-average interest rate on outstanding borrowings																																						2.27%
Amount of letter of credit issued that supports this credit facility																																																300,000,000
Capacity of seperate credit agreement which supports this credit facility																																																300,000,000
Term of separate credit agreement which supports this credit facility																																																5
Expiration date of separate credit agreement which supports this credit facility																																																March 2011
Deferred fees, written-off, in connection with the reduction in credit facility capacity																																						10,000,000
Deferred fees, after-tax, written-off, in connection with the reduction in credit facility capacity																																						6,000,000
Accounts receivable pledged under the credit facility																																																										251,000,000		248,000,000
Unbilled revenue pledged under the credit facility																																																										98,000,000		133,000,000
Maximum percentage of debt to total capitalization allowed under the credit facility																																				65.00%																		70.00%										70.00%										70.00%				70.00%
Potential maximum Facility Agreement capacity																																														500,000,000
Aggregate carrying value of mortgages																																															2,700,000,000
Potential capacity increase																																				500,000,000																		100,000,000										100,000,000										100,000,000
Automatic renewal term (in years)																																															1
Available capacity under PPL Electric asset-backed credit facility																																																										103,000,000
Deferred fees													7,000,000																									41,000,000																		2,000,000
The original capacity of the facility, prior to the reduction																																						4,000,000,000
Short-term Debt [Line Items]
Capacity																																			500,000,000																		200,000,000								250,000,000										250,000,000
Original committed capacity of Bridge Facility		3,600,000,000
Fees incurrred in connection with Bridge Facility	44,000,000
Interest rate on facility (in hundredths)																																																																															2.62%	2.62%			2.62%
Libor rates for borrowings	one-month LIBOR plus a spread
Borrowings during period on short-term facility																																																																																1,750,000,000			1,850,000,000
Repayments during period on short-term facility																																																																															2,800,000,000		1,200,000,000	650,000,000
Commercial paper outstanding																																			$ 400,000,000
Weighted-average interest rate on outstanding commercial paper																																			0.53%

[1] Under this facility, PPL WW has the ability to make cash borrowings but cannot request the lenders to issue letters of credit. PPL WW pays customary commitment fees under this facility, and borrowings bear interest at LIBOR-based rates plus a spread, depending on the company's long-term credit rating. The cash borrowing outstanding at December 31, 2011 was a USD-denominated borrowing of $178 million, which equated to £111 million at the time of borrowing and bears interest at approximately 1.05%. The interest rates at December 31, 2010 were approximately 0.94% on a USD-denominated borrowing of $181 million, which equated to £115 million at the time of borrowing. This credit facility contains financial covenants that require PPL WW to maintain an interest coverage ratio of not less than 3.0 times consolidated earnings before income taxes, depreciation and amortization and a RAV that exceeds total net debt by the higher of an amount equal to 15% of total net debt or £150 million, in each case as calculated in accordance with the credit facility.

[2] Under this 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 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. In January 2012, WPD (South West) entered into a new £245 million syndicated credit facility to replace its existing £210 million syndicated credit facility. Under the new 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 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.

[3] In April 2011, following the completion of the acquisition of WPD Midlands, WPD (East Midlands) and WPD (West Midlands) each entered into a £300 million 5-year syndicated credit facility. Under the facilities, WPD (East Midlands) and WPD (West Midlands) each have the ability to make cash borrowings and to request the lenders to issue up to £80 million of letters of credit in lieu of borrowing. Each company pays customary commitment and utilization fees under its respective facility and borrowings generally bear interest at LIBOR-based rates plus a spread, depending upon the respective company's senior unsecured long-term debt rating. Each credit facility contains financial covenants that require the respective company to maintain an interest coverage ratio of not less than 3.0 times consolidated earnings before interest, 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 facilities. An aggregate of $7 million in fees were incurred in connection with establishing these facilities.

[4] The total amount borrowed under WPD's credit facilities equated to $178 million and approximately $181 million at December 31, 2011 and 2010. At December 31, 2011, the unused capacity of WPD's credit facilities was approximately $1.2 billion. As a result of PPL Energy Supply's January 2011 distribution of its membership interest in PPL Global to its parent, PPL Energy Funding, the assets and liabilities of PPL Global, including the total amount borrowed under WPD's credit facilities at December 31, 2010 were removed from PPL Energy Supply's balance sheet in 2011. See Note 9 for additional information.

[5] 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.

[6] In October 2011, PPL Energy Supply, PPL Electric, LG&E and KU each amended its respective credit facility. The amendments include extending the expiration dates from December 2014 to October 2016. Under these credit facilities, PPL Energy Supply, PPL Electric, LG&E and KU each continue to have the ability to make cash borrowings and request the lenders to issue letters of credit.

[7] Under this facility, PPL Energy Supply has the ability to make cash borrowings and to request the lenders to issue letters of credit. Borrowings generally bear interest at LIBOR-based rates plus a spread, depending upon the company's senior unsecured long-term debt rating. PPL Energy Supply also pays customary commitment and letter of credit issuance fees under this facility. The credit facility contains a financial covenant requiring PPL Energy Supply's debt to total capitalization not to exceed 65%, as calculated in accordance with the facility, and other customary covenants. Additionally, subject to certain conditions, PPL Energy Supply may request that the facility's capacity be increased by up to $500 million. In October 2010, PPL Energy Supply borrowed $3.2 billion under this facility in order to enable a subsidiary to make loans to certain affiliates to provide interim financing of amounts required by PPL to partially fund PPL's acquisition of LKE. Such borrowing bore interest at 2.26% and was refinanced primarily through the issuance of long-term debt by LKE, LG&E, and KU and the use of internal funds. This borrowing and related payments were included in "Net increase (decrease) in short-term debt" on the Statement of Cash Flows. PPL Energy Supply incurred an aggregate of $41 million of fees in 2010 in connection with establishing this facility. Such fees were initially deferred and amortized through December 2014. In connection with the reduction in the capacity from $4 billion to $3 billion in December 2010, PPL Energy Supply wrote off $10 million, $6 million after tax, of deferred fees, which was reflected in "Interest Expense" in the Statement of Income. The borrowings outstanding at December 31, 2010 bore interest at a weighted-average rate of 2.27%.

[8] Under this facility, PPL Electric has the ability to make cash borrowings and to request the lenders to issue letters of credit. Borrowings generally bear interest at LIBOR-based rates plus a spread, depending upon the company's senior secured long-term debt rating. The credit facility contains a financial covenant requiring PPL Electric's debt to total capitalization not to exceed 70%, as calculated in accordance with the credit facility, and other customary covenants. PPL Electric also pays customary commitment and letter of credit issuance fees under this facility. Additionally, subject to certain conditions, PPL Electric may request that the facility's capacity be increased by up to $100 million. An aggregate of $2 million of fees were incurred in 2010 in connection with establishing this facility. Such fees were initially deferred and amortized through December 2014.

[9] 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 December 31, 2011 and December 31, 2010, $251 million and $248 million of accounts receivable and $98 million and $133 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 December 31, 2011, the amount available for borrowing under the facility was limited to $103 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. In July 2011, PPL Electric and the subsidiary extended the expiration date of the credit agreement to July 2012.

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

[11] In June 2011, these facilities were amended such that the fees and the spreads to benchmark interest rates for borrowings depend upon the respective company's senior secured long-term debt rating rather than the senior unsecured long-term debt rating. The facilities each contain a financial covenant requiring LG&E's and KU's debt to total capitalization not to exceed 70%, as calculated in accordance with the facilities, and other customary covenants. Additionally, subject to certain conditions, LG&E and KU may request that each respective facility's capacity be increased by up to $100 million.

[12] In April 2011, KU entered into a letter of credit facility that has been used to issue letters of credit to support outstanding tax-exempt bonds. The facility contains a financial covenant requiring KU's debt to total capitalization not to exceed 70%, as calculated in accordance with the credit facility. KU pays customary commitment and letter of credit fees under the new facility. In August 2011, KU amended its letter of credit facility such that the fees depend upon KU's senior secured long-term debt rating rather than its senior unsecured long-term debt rating.

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

[14] The borrowing outstanding at December 31, 2010 bore interest at 2.27%. Such borrowing was repaid in January 2011 with proceeds received from the remarketing of certain tax-exempt bonds that were held by LG&E at December 31, 2010.

[15] In March 2011, PPL Energy Supply's $300 million Structured Credit Facility expired. PPL Energy Supply's obligations under this facility were supported by a $300 million letter of credit issued on PPL Energy Supply's behalf under a separate but related $300 million 5-year credit agreement, which also expired in March 2011.