Retirement and Postemployment Benefits (Plan Assets and Expected Cash Flows) (Details) $ in Millions		12 Months Ended
		Dec. 31, 2015 USD ($) Integer	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)		Dec. 31, 2014 USD ($)
Pension Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 4,462	$ 4,462	$ 3,227		$ 4,462
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		4,462	4,009
Balance at end of period		3,227	4,462
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 30
Expected amount of benefit payments in the next period for non-qualified plans				10
Estimated Future Benefit Payments (Details) [Abstract]
2016				234
2017				245
2018				250
2019				259
2020				261
2021-2025				1,333
Pension Benefits United States [Member] | Master Trust [Member]
Assumptions Used in Calculations (Numeric) [Abstract]
The limited lives of four partnership of private equity investments (in years)		10
The limited lives of fifth partnership of private equity investments (in years)		15
The amount of potential liability that maybe required to be funded by the master trust during life of the partnership				$ 27
Minimum number of days notice required to redeem shares for investments in hedge funds | Integer		60
Maximum number of days notice required to redeem shares for investments in hedge funds | Integer		95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				100.00%	[1]	100.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	100.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 3,387	4,809	$ 3,387		$ 4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		4,809
Balance at end of period		3,387	4,809
Expected Federal Subsidy (Details) [Abstract]
Assets transferred to Talen Energy as a result of the spinoff				1,159
Assets transferred to Talen Energy for PPL Montana				170
Pension Benefits United States [Member] | Master Trust [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		1,211	1,211	889		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,211
Balance at end of period		889	1,211
Pension Benefits United States [Member] | Master Trust [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		1,228	1,228	851		1,228
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,228
Balance at end of period		851	1,228
Pension Benefits United States [Member] | Master Trust [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		54	54	42		54
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		54	60
Actual return on plan assets relating to assets still held at the reporting date		2	0
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(13)	(5)
Balance at end of period		42	54
Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			197		318
Measured at fair value not using net asset value per share				87		114
Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				87		114
Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			454		615
Pension Benefits United States [Member] | Master Trust [Member] | Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			514		818
Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				501		723
Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				492		706
Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				9		17
Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				747		1,109
Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				737		1,088
Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				10		21
Fair value at end of period			23
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			23
Actual return on plan assets relating to assets still held at the reporting date		0	(1)
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(10)	0
Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			70		90
Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			118		148
Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			81		104
Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			171		223
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
Fair value at end of period			37
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			37
Actual return on plan assets relating to assets still held at the reporting date		2	1
Actual return on plan assets relating to assets sold during the period		0	0
Purchases, sales and settlements		(3)	(5)
Pension Benefits United States [Member] | Master Trust [Member] | Receivables And Payables Net [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[3]	(41)	(41)	(49)		(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[3]	(41)
Balance at end of period	[3]	(49)	(41)
Pension Benefits United States [Member] | Master Trust [Member] | Account 401 H [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		(136)	(136)	(111)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		(136)
Balance at end of period		(111)	(136)
Pension Benefits United States [Member] | Master Trust [Member] | Total Trust Assets Not Including 401 H Assets [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[4]	4,632	4,632	$ 3,227		$ 4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[4]	4,632
Balance at end of period	[4]	$ 3,227	4,632
Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				51.00%	[1]	51.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	50.00%
Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				25.00%	[1]	26.00%
Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			13.00%	[1]	13.00%
Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Alternative Investments [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				13.00%	[1]	12.00%
Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				47.00%	[1]	47.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	48.00%
Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			42.00%	[1]	44.00%
Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Derivatives [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				5.00%	[1]	3.00%
Pension Benefits United States [Member] | Master Trust [Member] | Liquidity Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				2.00%	[1]	2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	2.00%
Pension Benefits United Kingdom [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				100.00%		100.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		100.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 7,734	7,284	$ 7,625		$ 7,734
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		7,734	7,284
Balance at end of period		7,625	7,734
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 364
Recurrence of formal actuarial valuations (in years) | Integer		3
Percentage of deficit funding requirements permitted to recover in rates		78.00%
Estimated Future Benefit Payments (Details) [Abstract]
2016				379
2017				384
2018				391
2019				397
2020				402
2021-2025				2,074
Pension Benefits United Kingdom [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 55	57	55		57
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		57
Balance at end of period		55	57
Pension Benefits United Kingdom [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		2,271	2,271	3,009		2,271
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		2,271
Balance at end of period		3,009	2,271
Pension Benefits United Kingdom [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		0	0	$ 0		$ 0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		0
Balance at end of period		$ 0	0
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				1.00%		1.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		0.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				$ 55		$ 57
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				55		57
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				$ 0		$ 0
Pension Benefits United Kingdom [Member] | UK Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				3.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		4.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 274		$ 239
Pension Benefits United Kingdom [Member] | European Companies Excluding UK Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				2.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 190		$ 198
Pension Benefits United Kingdom [Member] | Asian Pacific Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				2.00%		2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		2.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 132		$ 142
Pension Benefits United Kingdom [Member] | North American Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				3.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 220		$ 227
Pension Benefits United Kingdom [Member] | Emerging Markets Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				10.00%		9.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		10.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 284		$ 309
Pension Benefits United Kingdom [Member] | Global Equities Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 500		$ 397
Pension Benefits United Kingdom [Member] | Currency Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				1.00%		2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		1.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 39		$ 190
Pension Benefits United Kingdom [Member] | Global Tactical Asset Allocation Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				31.00%		29.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		31.00%
Pension Benefits United Kingdom [Member] | Other Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share				$ 2,384		$ 2,263
Pension Benefits United Kingdom [Member] | UK Corporate Bonds Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share				92		2
Pension Benefits United Kingdom [Member] | UK Gilts Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share				$ 3		$ 913
Pension Benefits United Kingdom [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[7]			40.00%		42.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[7]	39.00%
Pension Benefits United Kingdom [Member] | United Kingdom Corporate Bonds Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				$ 364		$ 344
Pension Benefits United Kingdom [Member] | United Kingdom Corporate Bonds Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United Kingdom [Member] | United Kingdom Corporate Bonds Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				364		344
Pension Benefits United Kingdom [Member] | United Kingdom Corporate Bonds Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United Kingdom [Member] | United Kingdom Gilts Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				2,645		1,927
Pension Benefits United Kingdom [Member] | United Kingdom Gilts Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Pension Benefits United Kingdom [Member] | United Kingdom Gilts Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				2,645		1,927
Pension Benefits United Kingdom [Member] | United Kingdom Gilts Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				$ 0		$ 0
Pension Benefits United Kingdom [Member] | Alternative Investments [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				7.00%		6.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		7.00%
Pension Benefits United Kingdom [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[6]			$ 533		$ 436
Other Postretirement Benefits United States [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				100.00%		100.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		100.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 379	446	$ 379		$ 484
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		484	446
Balance at end of period		379	484
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 13
Estimated Future Benefit Payments (Details) [Abstract]
2016				54
2017				53
2018				53
2019				53
2020				52
2021-2025				244
Expected Federal Subsidy (Details) [Abstract]
Federal subsidy 2016				1
Federal subsidy 2017				1
Federal subsidy 2018				1
Federal subsidy 2019				1
Federal subsidy 2020				1
Federal subsidy 2021-2025				2
Assets transferred to Talen Energy as a result of the spinoff				$ 80
Other Postretirement Benefits United States [Member] | Cash And Cash Equivalents [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[8]			2.00%		2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[8]	5.00%
Other Postretirement Benefits United States [Member] | Money Market Funds [Member]
Assumptions Used in Calculations (Numeric) [Abstract]
Number of months from date of purchase that investment must mature | Integer		13
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 9	9	$ 6		$ 9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		9
Balance at end of period		$ 6	9
Other Postretirement Benefits United States [Member] | Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				48.00%		49.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average		45.00%
Other Postretirement Benefits United States [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[9]			50.00%		49.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[9]	50.00%
Other Postretirement Benefits United States [Member] | Receivables And Payables Net [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 1	1	$ 1		$ 1
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1
Balance at end of period		1	1
Other Postretirement Benefits United States [Member] | Account 401 H [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		136	136	111		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		136
Balance at end of period		111	136
Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		267	347	267		347
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		347
Balance at end of period		267	347
Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		9	9	6		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		9
Balance at end of period		6	9
Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		23	33	23		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		33
Balance at end of period		23	33
Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		0	0	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		0
Balance at end of period		0	0
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Money Market Funds [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				6		9
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Money Market Funds [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Money Market Funds [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Other Postretirement Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[10]			129		169
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share				109		136
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Municipalities Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				23		33
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Municipalities Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Municipalities Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				23		33
Other Postretirement Benefits United States [Member] | Master Trust [Member] | Municipalities Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		1,289	1,173	1,289		1,301
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,301	1,173
Balance at end of period		1,289	$ 1,301
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 30
Expected amount of benefit payments in the next period for non-qualified plans				3
Estimated Future Benefit Payments (Details) [Abstract]
2016				95
2017				100
2018				102
2019				105
2020				107
2021-2025				550
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member]
Information About Plan Assets (Numeric) [Abstract]
Value of plan U.S. pension trust assets that relate to PPL subsidiary				1,300		$ 1,300
Undivided interest percentage in each asset category that PPL subsidiary holds		40.00%	28.00%
Assumptions Used in Calculations (Numeric) [Abstract]
The limited lives of four partnership of private equity investments (in years)		10
The limited lives of fifth partnership of private equity investments (in years)		15
The amount of potential liability that maybe required to be funded by the master trust during life of the partnership				$ 27
Minimum number of days notice required to redeem shares for investments in hedge funds | Integer		60
Maximum number of days notice required to redeem shares for investments in hedge funds | Integer		95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				100.00%	[1]	100.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	100.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 3,387	$ 4,809	$ 3,387		$ 4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		4,809
Balance at end of period		3,387	4,809
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		889	1,211	889		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,211
Balance at end of period		889	1,211
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		1,228	1,228	851		1,228
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,228
Balance at end of period		851	1,228
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		42	54	42		54
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		54	60
Actual return on plan assets relating to assets still held at the reporting date		2	0
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(13)	(5)
Balance at end of period		42	54
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			197		318
Measured at fair value not using net asset value per share				87		114
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				87		114
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			454		615
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			514		818
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				501		723
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				492		706
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				9		17
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				747		1,109
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				737		1,088
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				10		21
Fair value at end of period			23
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			23
Actual return on plan assets relating to assets still held at the reporting date		0	(1)
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(10)	0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			70		90
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			118		148
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			81		104
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			171		223
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
Fair value at end of period			37
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			37
Actual return on plan assets relating to assets still held at the reporting date		2	1
Actual return on plan assets relating to assets sold during the period		0	0
Purchases, sales and settlements		(3)	(5)
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Receivables And Payables Net [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[3]	(41)	(41)	(49)		(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[3]	(41)
Balance at end of period	[3]	(49)	(41)
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Account 401 H [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		(136)	(136)	(111)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		(136)
Balance at end of period		(111)	(136)
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Total Trust Assets Not Including 401 H Assets [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[4]	4,632	4,632	$ 3,227		$ 4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[4]	4,632
Balance at end of period	[4]	$ 3,227	4,632
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				51.00%	[1]	51.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	50.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				25.00%	[1]	26.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			13.00%	[1]	13.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Alternative Investments [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				13.00%	[1]	12.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				47.00%	[1]	47.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	48.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			42.00%	[1]	44.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Derivatives [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				5.00%	[1]	3.00%
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Liquidity Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				2.00%	[1]	2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	2.00%
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 88	74	$ 88		$ 82
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		82	74
Balance at end of period		88	82
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 13
Estimated Future Benefit Payments (Details) [Abstract]
2016				13
2017				14
2018				15
2019				16
2020				16
2021-2025				85
Expected Federal Subsidy (Details) [Abstract]
Federal subsidy 2016				0
Federal subsidy 2017				0
Federal subsidy 2018				1
Federal subsidy 2019				0
Federal subsidy 2020				0
Federal subsidy 2021-2025				2
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Money Market Funds [Member]
Assumptions Used in Calculations (Numeric) [Abstract]
Number of months from date of purchase that investment must mature | Integer		13
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 6	9	6		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		9
Balance at end of period		6	9
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		347	347	267		347
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		347
Balance at end of period		267	347
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		6	9	6		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		9
Balance at end of period		6	9
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		23	33	23		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		33
Balance at end of period		23	33
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Total Trust Assets Not Including 401 H Assets [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		0	0	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		0
Balance at end of period		0	0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		297	281	297		301
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		301	281
Balance at end of period		297	$ 301
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year		$ 7
Estimated Future Benefit Payments (Details) [Abstract]
2016				23
2017				25
2018				24
2019				25
2020				25
2021-2025				111
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member]
Information About Plan Assets (Numeric) [Abstract]
Value of plan U.S. pension trust assets that relate to PPL subsidiary				297		$ 301
Undivided interest percentage in each asset category that PPL subsidiary holds		9.00%	6.00%
Assumptions Used in Calculations (Numeric) [Abstract]
The limited lives of four partnership of private equity investments (in years)		10
The limited lives of fifth partnership of private equity investments (in years)		15
The amount of potential liability that maybe required to be funded by the master trust during life of the partnership				$ 27
Minimum number of days notice required to redeem shares for investments in hedge funds | Integer		60
Maximum number of days notice required to redeem shares for investments in hedge funds | Integer		95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				100.00%	[1]	100.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	100.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		$ 3,387	$ 4,809	$ 3,387		$ 4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		4,809
Balance at end of period		3,387	4,809
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		889	1,211	889		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,211
Balance at end of period		889	1,211
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		1,228	1,228	851		1,228
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		1,228
Balance at end of period		851	1,228
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		54	54	42		54
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		54	60
Actual return on plan assets relating to assets still held at the reporting date		2	0
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(13)	(5)
Balance at end of period		42	54
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				225		246
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			197		318
Measured at fair value not using net asset value per share				87		114
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				87		114
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Large Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				85		145
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Small Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			454		615
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			514		818
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				501		723
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				492		706
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				9		17
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | US Treasury And US Government Sponsored Agency Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				3		2
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Residential - Commercial Backed Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				747		1,109
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				737		1,088
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				10		21
Fair value at end of period			23
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			23
Actual return on plan assets relating to assets still held at the reporting date		0	(1)
Actual return on plan assets relating to assets sold during the period		(1)	(1)
Purchases, sales and settlements		(10)	0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				4		8
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Government Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				7		9
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			70		90
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			118		148
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			81		104
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value using net asset value per share	[2]			171		223
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				80		92
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps And Swaptions Derivatives [ Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				11		12
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Measured at fair value not using net asset value per share				32		33
Fair value at end of period			37
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			37
Actual return on plan assets relating to assets still held at the reporting date		2	1
Actual return on plan assets relating to assets sold during the period		0	0
Purchases, sales and settlements		(3)	(5)
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Receivables And Payables Net [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[3]	(41)	(41)	(49)		(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[3]	(41)
Balance at end of period	[3]	(49)	(41)
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Account 401 H [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period		(136)	(136)	(111)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period		(136)
Balance at end of period		(111)	(136)
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Total Trust Assets Not Including 401 H Assets [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	[4]	4,632	4,632	$ 3,227		$ 4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	[4]	4,632
Balance at end of period	[4]	$ 3,227	$ 4,632
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				51.00%	[1]	51.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	50.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				25.00%	[1]	26.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			13.00%	[1]	13.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member] | Alternative Investments [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				13.00%	[1]	12.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				47.00%	[1]	47.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	48.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	[5]			42.00%	[1]	44.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Derivatives [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				5.00%	[1]	3.00%
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Liquidity Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets				2.00%	[1]	2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average	[1]	2.00%

[1] Allocations exclude consideration of a group annuity contract held by the LG&E and KU Retirement Plan.

[2] In accordance with accounting guidance certain investments that are measured at fair value using the net asset value per share (NAV), or its equivalent, practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position.

[3] Receivables and payables represent amounts for investments sold/purchased but not yet settled alon g with interest and dividends earned but not yet received.

[4] As a result of the spinoff of PPL Energy Supply, $1,159 million of assets were transferred to Talen Energy in 2015, attributable to former active and inactive employees of PPL Energy Supply that had participated in PPL’s pension plan. An additional $170 million of assets of the PPL Montana pension plan transferred to Talen Energy, as that entire plan was assumed by Talen Energy.

[5] Includes commingled debt funds, which PPL treats as debt securities for asset allocation purposes .

[6] In accordance with accounting guidance certain investments that are measured at fair value using the net asset value per share (NAV), or its equivalent, practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position.

[7] Includes commingled debt funds.

[8] Includes money market fund s .

[9] Includes commingled debt funds and debt securities.

[10] In accordance with accounting guidance certain investments that are measured at fair value using the net asset value per share (NAV), or its equivalent, practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position.