Acquisitions, Development and Divestures (Details) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2015 USD ($) Integer shares		Mar. 31, 2015 Integer	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Integer MW shares		Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Results of Discontinued Operations (Details) [Abstract]
Income (Loss) from Discontinued Operations (net of income taxes)		$ (1,007)			$ (1)	$ (912)		$ (74)
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Total Current Assets		0				0			$ 2,600
Total Noncurrent Assets		0				0			8,317
Total Current Liabilities		0				0			2,775
Accrued pension obligations		244				244
Total Nonurrent Liabilities		0				$ 0			3,963
Solar Generation Facility [Member]
Development Projects [Abstract]
Planned capacity expansion (in MW) | MW						10
Expected capital cost of an expansion project		36				$ 36
Spinoff [Member] | PPL Energy Supply Spinoff [Member]
Discontinued Operations - Spinoff of PPL Energy Supply - Cost of Spinoff (Numberic) [Abstract]
Amount of accrued libality for seperation benefits		13				13			21
Spinoff transaction costs		36			16	42		16
Spinoff [Member] | PPL Energy Supply Spinoff [Member] | Other Operation And Maintenance [Member]
Discontinued Operations - Spinoff of PPL Energy Supply - Cost of Spinoff (Numberic) [Abstract]
Spinoff transaction costs		7				11
Spinoff [Member] | PPL Energy Supply Spinoff [Member] | Discontinued Operations [Member]
Discontinued Operations - Spinoff of PPL Energy Supply - Cost of Spinoff (Numberic) [Abstract]
Seperation benefits						24
Spinoff transaction costs		$ 29				$ 31
PPL Energy Supply Spinoff [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Spinoff agreement execution date						Jun. 09, 2014
Date of record						May 20, 2015
Effective date of spinoff						Jun. 01, 2015
Certain details of spinoff transaction						In June 2014, PPL and PPL Energy Supply executed definitive agreements with affiliates of Riverstone to spin off PPL Energy Supply and immediately combine it with Riverstone’s competitive power generation businesses to form a new, stand-alone, publicly traded company named Talen Energy. The transaction was subject to customary closing conditions, including receipt of regulatory approvals from the NRC, FERC, DOJ and PUC, all of which were received by mid-April 2015. On April 29, 2015, PPL’s Board of Directors declared the June 1, 2015 distribution to PPL’s shareowners of record on May 20, 2015 of a newly formed entity, Holdco, which at closing owned all of the membership interests of PPL Energy Supply and all of the common stock of Talen Energy.
Number of shares of Talen common stock for one share of PPL common stock | shares		0.1249				0.1249
Initial percent ownership in new company, Talen Energy, by PPL shareowners						65.00%
Initial percent ownership in new company, Talen Energy, by Riverstone Holdings, LLC						35.00%
Number of approaches | Integer						3
Weighted fair value		$ 3,224				$ 3,224
Control premium						25.00%
Number of market approaches | Integer						2
Review period used in determing the control premium (in years)						05 years
Mimimum transaction value reviewed in determining the control premium						$ 1,000
Carrying value of the Supply segment		4,100				4,100
Gain (loss) recognized in discontinued operations on the statement of income						72
Gain (loss), after-tax, recognized in discontinued operations on the statement of income						$ 42
Maximum period for Transition Service Agreement (in years)						02 years
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Results of Discontinued Operations (Details) [Abstract]
Operating revenues		483			1,046	$ 1,427		118
Operating expenses		561			1,006	1,328		164
Other Income (Expense) - net		(29)			(8)	(22)		(2)
Interest Expense	[1]	112			50	150		98
Income (loss) before income taxes		(219)			(18)	(73)		(146)
Income tax expense (benefit)		(91)			(17)	(40)		(72)
Loss on spinoff		(879)			0	(879)		0
Income (Loss) from Discontinued Operations (net of income taxes)		(1,007)			(1)	(912)		(74)
Discontinued Operations - Spinoff of PPL Energy Supply - Summarized Assets and Liabilities of Discontinued Operations (Details) [Abstract]
Cash and cash equivalents		371	[2]			371	[2]		352
Restricted cash and cash equivalents		156				156			176
Accounts receivable and unbilled revenues		325				325			504
Fuels, materials and supplies		415				415			455
Price risk management assets		784				784			1,079
Other current assets		65				65			34
Total Current Assets		2,116				2,116			2,600
Investments		999				999			980
Property Plant and Equipment, net		6,384				6,384			6,428
Goodwill		338				338			338
Other intangibles		260				260			257
Price risk management assets		244				244			239
Other noncurrent assets		78				78			75
Total Noncurrent Assets		8,303				8,303			8,317
Total assets		10,419				10,419			10,917
Short-term debt and long-term debt due within one year		885				885			1,165
Accounts payable		252				252			361
Price risk management liabilities		763				763			1,024
Other current liabilities		229				229			225
Total Current Liabilities		2,129				2,129			2,775
Long-term debt (excluding current portion)		1,932				1,932			1,683
Deferred income taxes		1,259				1,259			1,223
Price risk management liabilities		206				206			193
Accrued pension obligations		244				244			299
Asset retirement obligations		443				443			415
Other deferred credits and noncurrent liabilities		103				103			150
Total Nonurrent Liabilities		4,187				4,187			3,963
Total liabilities		6,316				6,316			$ 6,738
Adjustment for loss on spinoff		879			$ 0	879		$ 0
Net assets distributed		$ 3,224				$ 3,224
PPL Energy Supply Spinoff [Member] | Minimum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control premium						5.00%
PPL Energy Supply Spinoff [Member] | Maximum [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Control premium						42.00%
PPL Energy Supply Spinoff [Member] | Talen Energy Market Value [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting						50.00%
PPL Energy Supply Spinoff [Member] | Income Discounted Cash Flow [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting						30.00%
PPL Energy Supply Spinoff [Member] | Alternative Market Comparable Company [Member]
Discontinued Operations - Spinoff of PPL Energy Supply (Numeric) [Abstract]
Weighting						20.00%
Montana Hydroelectric Generating Facilities [Member]
Divestitures - Montana Hydro Sale Agreement (Numeric) [Abstract]
Capacity of facilities sold (in MW) | MW						633
Agreed upon sales price for disposal of hydroelectric facilities owned by PPL Montana						$ 900
Number of hydroelectric facilities owned by PPL Montana sold | Integer		11				11
LGE [Member]
Development Projects [Abstract]
Generating units retired at the Cane Run plant | Integer		2		1
Loss from retirement of coal-fired generating units						$ 11
LG And E And KU Energy LLC [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Planned capacity expansion (in MW) | MW						10
Expected capital cost of an expansion project		$ 36				$ 36
LG And E And KU Energy LLC [Member] | LGE [Member]
Development Projects [Abstract]
Generating units retired at the Cane Run plant | Integer		2		1
Loss from retirement of coal-fired generating units						11
Louisville Gas And Electric Co [Member]
Development Projects [Abstract]
Generating units retired at the Cane Run plant | Integer		2		1
Loss from retirement of coal-fired generating units						$ 11
Louisville Gas And Electric Co [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Planned capacity expansion (in MW) | MW						10
Expected capital cost of an expansion project		$ 36				$ 36
Kentucky Utilities Co [Member] | Solar Generation Facility [Member]
Development Projects [Abstract]
Planned capacity expansion (in MW) | MW						10
Expected capital cost of an expansion project		$ 36				$ 36

[1] Includes interest associated with the Supply Segment with no additional allocation as the Supply segment was sufficiently capitalized.

[2] The distribution of PPL Energy Supply ’s cash and cash equivalents at June 1, 2015 is included in "Net cash provided by (used in) financing activities - discontinu ed operations" on the Statement of Cash Flows for the six months ended June 30, 2015 .