Retirement and Postemployment Benefits (Plan Assets and Expected Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2014		Dec. 31, 2012
Master Trust [Member] | Other Debt Securities [Member] | Level 3 [Member]
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Actual return on plan assets relating to assets still held at the reporting date	$ 0
Pension Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			4,632		3,939
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			4,156		3,939
Balance at end of period			4,632		3,939
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year			175
Expected amount of benefit payments in the next period for non-qualified plans			10
Estimated Future Benefit Payments (Details) [Abstract]
2015			268
2016			279
2017			294
2018			308
2019			323
2020-2024			1,749
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			55
Minimum number of days notice required to redeem shares for investments in hedge funds			65
Maximum number of days notice required to redeem shares for investments in hedge funds			95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	100.00%		100.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			100.00%	[1]
Target asset allocation - PPL Plans			100.00%	[1]
Target asset allocation - LKE Plans			100.00%	[1]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			4,271
Balance at end of period			4,809
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	1,130		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,130		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	3,000		3,440
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	3,000		3,440
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	141		158
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	146		141
Actual return on plan assets relating to assets still held at the reporting date	5		18
Actual return on plan assets relating to assets sold during the period	5		(1)
Purchases, sales and settlements	(14)		0
Transfers from level 3 to level 2	(1)
Balance at end of period	141		158
Pension Benefits United States [Member] | Master Trust [Member] | Cash And Cash Equivalents [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	480		432
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	480		432
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]
Fair value at end of period	134		114
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		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]
Fair value at end of period	346		318
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	346		318
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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	749		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	749		818
Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	13		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	13		0
Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	736		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	736		818
Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	630		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	630		615
Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	163		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	163		0
Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	467		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	467		615
Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	617		723
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	617		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]
Fair value at end of period	563		706
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	563		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]
Fair value at end of period	54		17
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	54		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	11		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	11		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]
Fair value at end of period	1		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1		1
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	0		0
Purchases, sales and settlements	0		0
Transfers from level 3 to level 2	0
Balance at end of period	1		0
Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	963		1,109
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	963		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	940		1,088
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	940		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]
Fair value at end of period	23		21
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	27		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	5		(1)
Purchases, sales and settlements	(9)		0
Transfers from level 3 to level 2	0
Balance at end of period	23		21
Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1
Actual return on plan assets relating to assets sold during the period	0
Purchases, sales and settlements	0
Transfers from level 3 to level 2	(1)
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	80		104
Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	75		80
Actual return on plan assets relating to assets still held at the reporting date	3		19
Actual return on plan assets relating to assets sold during the period	0		0
Purchases, sales and settlements	2		5
Transfers from level 3 to level 2	0
Balance at end of period	80		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]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	37		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	42		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	(7)		(5)
Transfers from level 3 to level 2	0
Balance at end of period	37		33
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	0	[2]	(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0	[2]	(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	(115)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(115)		(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	4,156		4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	4,156		4,632
Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	59.00%		51.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			52.00%	[1]
Target asset allocation - PPL Plans			52.00%	[1]
Target asset allocation - LKE Plans			52.00%	[1]
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	30.00%		26.00%	[1]
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	17.00%	[3]	13.00%	[1],[3]
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	12.00%		12.00%	[1]
Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	39.00%		47.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			46.00%	[1]
Target asset allocation - PPL Plans			46.00%	[1]
Target asset allocation - LKE Plans			46.00%	[1]
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	40.00%	[3]	44.00%	[1],[3]
Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member] | Derivatives [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	(1.00%)		3.00%	[1]
Pension Benefits United States [Member] | Master Trust [Member] | Liquidity Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	2.00%		2.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			2.00%	[1]
Target asset allocation - PPL Plans			2.00%	[1]
Target asset allocation - LKE Plans			2.00%	[1]
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		6,911
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			7,284		6,911
Balance at end of period			7,734		6,911
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year			377
Recurrence of formal actuarial valuations (in years)			3
Percentage of deficit funding requirements permitted to recover in rates			64.00%
Approximate percentage of WPD's pension funding requirements that will be permitted to be recovered in rates in 2019			80.00%
Estimated Future Benefit Payments (Details) [Abstract]
2015			386
2016			391
2017			395
2018			403
2019			409
2020-2024			2,118
Pension Benefits United Kingdom [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	1,112		57
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,112		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	6,172		7,677
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	6,172		7,677
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
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
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	0.00%		1.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			0.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			57
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			10
Balance at end of period			57
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	10		57
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	10		57
Pension Benefits United Kingdom [Member] | Cash And Cash Equivalents [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | UK Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	7.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			239
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			523
Balance at end of period			239
Pension Benefits United Kingdom [Member] | UK Companies Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	267		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	267		0
Pension Benefits United Kingdom [Member] | UK Companies Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	256		239
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	256		239
Pension Benefits United Kingdom [Member] | UK Companies Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | European Companies Excluding UK Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	5.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			198
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			355
Balance at end of period			198
Pension Benefits United Kingdom [Member] | European Companies Excluding UK Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	275		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	275		0
Pension Benefits United Kingdom [Member] | European Companies Excluding UK Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		198
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	80		198
Pension Benefits United Kingdom [Member] | European Companies Excluding UK Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Asian Pacific Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	3.00%		2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			2.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			142
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			226
Balance at end of period			142
Pension Benefits United Kingdom [Member] | Asian Pacific Companies Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	180		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	180		0
Pension Benefits United Kingdom [Member] | Asian Pacific Companies Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	46		142
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	46		142
Pension Benefits United Kingdom [Member] | Asian Pacific Companies Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | North American Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	5.00%		3.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			227
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			352
Balance at end of period			227
Pension Benefits United Kingdom [Member] | North American Companies Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	254		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	254		0
Pension Benefits United Kingdom [Member] | North American Companies Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	98		227
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	98		227
Pension Benefits United Kingdom [Member] | North American Companies Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Emerging Markets Companies Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	8.00%		9.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			9.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			309
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			411
Balance at end of period			309
Pension Benefits United Kingdom [Member] | Emerging Markets Companies Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	126		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	126		0
Pension Benefits United Kingdom [Member] | Emerging Markets Companies Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	285		309
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	285		309
Pension Benefits United Kingdom [Member] | Emerging Markets Companies Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Global Equities Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	161		397
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	161		397
Pension Benefits United Kingdom [Member] | Global Equities Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	161		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	161		0
Pension Benefits United Kingdom [Member] | Global Equities Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		397
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		397
Pension Benefits United Kingdom [Member] | Global Equities Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Currency Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	7.00%		2.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			3.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			190
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			485
Balance at end of period			190
Pension Benefits United Kingdom [Member] | Currency Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Currency Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	485		190
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	485		190
Pension Benefits United Kingdom [Member] | Currency Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Global Tactical Asset Allocation Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	19.00%		29.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			30.00%
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			2,263
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			1,384
Balance at end of period			2,263
Pension Benefits United Kingdom [Member] | Global Tactical Asset Allocation Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Global Tactical Asset Allocation Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	1,384		2,263
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,384		2,263
Pension Benefits United Kingdom [Member] | Global Tactical Asset Allocation Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | UK Corporate Bonds Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	504		436
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	504		436
Pension Benefits United Kingdom [Member] | UK Corporate Bonds Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | UK Corporate Bonds Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	504		436
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	504		436
Pension Benefits United Kingdom [Member] | UK Corporate Bonds Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | UK Gilts Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	2,426		2,840
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	2,426		2,840
Pension Benefits United Kingdom [Member] | UK Gilts Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | UK Gilts Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	2,426		2,840
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	2,426		2,840
Pension Benefits United Kingdom [Member] | UK Gilts Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	40.00%	[4]	42.00%	[4]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			41.00%	[4]
Pension Benefits United Kingdom [Member] | Alternative Investments [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	6.00%		6.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			6.00%
Pension Benefits United Kingdom [Member] | Real Estate Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	447		436
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	447		436
Pension Benefits United Kingdom [Member] | Real Estate Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Pension Benefits United Kingdom [Member] | Real Estate Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	447		436
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	447		436
Pension Benefits United Kingdom [Member] | Real Estate Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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			484		421
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			446		421
Balance at end of period			484		421
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year			17
Estimated Future Benefit Payments (Details) [Abstract]
2015			54
2016			56
2017			58
2018			60
2019			62
2020-2024			326
Expected Federal Subsidy (Details) [Abstract]
Federal subsidy 2015			1
Federal subsidy 2016			1
Federal subsidy 2017			1
Federal subsidy 2018			1
Federal subsidy 2019			1
Federal subsidy 2020-2024			3
Other Postretirement Benefits United States [Member] | Cash And Cash Equivalents [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	4.00%	[5]	2.00%	[5]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			5.00%	[5]
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			13
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			12
Balance at end of period			9
Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	12		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		9
Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | Equity Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	55.00%		49.00%
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			45.00%
Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	182		169
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	182		169
Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	182		169
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	182		169
Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	100		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	100		136
Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	100		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	100		136
Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | Debt Securities [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	41.00%	[6]	49.00%	[6]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			50.00%	[6]
Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	36		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	36		33
Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	36		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	36		33
Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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	[7]	1	[7]
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1	[7]	1	[7]
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	115		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	115		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	330		347
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	330		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	12		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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	318		338
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	318		338
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
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			170		149
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			147		149
Balance at end of period			170		149
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year			32
Estimated Future Benefit Payments (Details) [Abstract]
2015			5
2016			7
2017			7
2018			8
2019			9
2020-2024			58
PPL Energy Supply 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	147		170
Undivided interest percentage in each asset category that PPL subsidiary holds	3.40%		4.00%
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			55
Minimum number of days notice required to redeem shares for investments in hedge funds			65
Maximum number of days notice required to redeem shares for investments in hedge funds			95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	100.00%		100.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			100.00%	[1]
Target asset allocation - PPL Plans			100.00%	[1]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	4,271		4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			4,271
Balance at end of period	4,271		4,809
PPL Energy Supply 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	1,130		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,130		1,211
PPL Energy Supply 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	3,000		3,440
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	3,000		3,440
PPL Energy Supply 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	141		158
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	146		141
Actual return on plan assets relating to assets still held at the reporting date	5		18
Actual return on plan assets relating to assets sold during the period	5		(1)
Purchases, sales and settlements	(14)		0
Transfers from level 3 to level 2	(1)
Balance at end of period	141		158
PPL Energy Supply 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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		246
PPL Energy Supply 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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		246
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	480		432
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	480		432
PPL Energy Supply 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]
Fair value at end of period	134		114
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		114
PPL Energy Supply 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]
Fair value at end of period	346		318
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	346		318
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		145
PPL Energy Supply 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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		145
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	749		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	749		818
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	13		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	13		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	736		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	736		818
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	630		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	630		615
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	163		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	163		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	467		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	467		615
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	617		723
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	617		723
PPL Energy Supply 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]
Fair value at end of period	563		706
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	563		706
PPL Energy Supply 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]
Fair value at end of period	54		17
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	54		17
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	12		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		2
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	11		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	11		2
PPL Energy Supply 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]
Fair value at end of period	1		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1		1
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	0		0
Purchases, sales and settlements	0		0
Transfers from level 3 to level 2	0
Balance at end of period	1		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Corporate Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	963		1,109
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	963		1,109
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	940		1,088
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	940		1,088
PPL Energy Supply 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]
Fair value at end of period	23		21
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	27		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	5		(1)
Purchases, sales and settlements	(9)		0
Transfers from level 3 to level 2	0
Balance at end of period	23		21
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		9
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		9
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1
Actual return on plan assets relating to assets still held at the reporting date	0
Actual return on plan assets relating to assets sold during the period	0
Purchases, sales and settlements	0
Transfers from level 3 to level 2	(1)
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	80		104
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	75		80
Actual return on plan assets relating to assets still held at the reporting date	3		19
Actual return on plan assets relating to assets sold during the period	0		0
Purchases, sales and settlements	2		5
Transfers from level 3 to level 2	0
Balance at end of period	80		104
PPL Energy Supply 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]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Other Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		12
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		12
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Insurance Contracts [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	37		33
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
PPL Energy Supply 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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	42		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	(7)		(5)
Transfers from level 3 to level 2	0
Balance at end of period	37		33
PPL Energy Supply 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	0	[2]	(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0	[2]	(41)
PPL Energy Supply 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	(115)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(115)		(136)
PPL Energy Supply 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	4,156		4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	4,156		4,632
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Growth Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	59.00%		51.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			52.00%	[1]
Target asset allocation - PPL Plans			52.00%	[1]
PPL Energy Supply 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	30.00%		26.00%	[1]
PPL Energy Supply 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	17.00%	[3]	13.00%	[1],[3]
PPL Energy Supply 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	12.00%		12.00%	[1]
PPL Energy Supply LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Immunizing Portfolio [Member]
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	39.00%		47.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			46.00%	[1]
Target asset allocation - PPL Plans			46.00%	[1]
PPL Energy Supply 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	40.00%	[3]	44.00%	[1],[3]
PPL Energy Supply 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	(1.00%)		3.00%	[1]
PPL Energy Supply 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%		2.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			2.00%	[1]
Target asset allocation - PPL Plans			2.00%	[1]
PPL Energy Supply LLC [Member] | Other Postretirement Benefits United States [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	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		0
Estimated Future Benefit Payments (Details) [Abstract]
2015			1
2016			1
2017			1
2018			2
2019			2
2020-2024			9
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			1,301		1,070
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			1,173		1,070
Balance at end of period			1,301		1,070
Defined Benefit Plan Estimated Future Employer Contributions (Numeric) [Abstract]
Amount to be contributed to plan in the next fiscal year			49
Expected amount of benefit payments in the next period for non-qualified plans			3
Estimated Future Benefit Payments (Details) [Abstract]
2015			60
2016			62
2017			67
2018			72
2019			77
2020-2024			456
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	1,200		1,300
Undivided interest percentage in each asset category that PPL subsidiary holds	29.00%		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			55
Minimum number of days notice required to redeem shares for investments in hedge funds			65
Maximum number of days notice required to redeem shares for investments in hedge funds			95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	100.00%		100.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			100.00%	[1]
Target asset allocation - LKE Plans			100.00%	[1]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	4,271		4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			4,271
Balance at end of period	4,271		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	1,130		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,130		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	3,000		3,440
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	3,000		3,440
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	141		158
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	146		141
Actual return on plan assets relating to assets still held at the reporting date	5		18
Actual return on plan assets relating to assets sold during the period	5		(1)
Purchases, sales and settlements	(14)		0
Transfers from level 3 to level 2	(1)
Balance at end of period	141		158
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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	480		432
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	480		432
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]
Fair value at end of period	134		114
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		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]
Fair value at end of period	346		318
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	346		318
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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	749		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	749		818
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	13		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	13		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	736		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	736		818
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	630		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	630		615
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	163		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	163		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	467		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	467		615
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	617		723
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	617		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]
Fair value at end of period	563		706
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	563		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]
Fair value at end of period	54		17
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	54		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	11		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	11		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]
Fair value at end of period	1		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1		1
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	0		0
Purchases, sales and settlements	0		0
Transfers from level 3 to level 2	0
Balance at end of period	1		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]
Fair value at end of period	963		1,109
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	963		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	940		1,088
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	940		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]
Fair value at end of period	23		21
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	27		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	5		(1)
Purchases, sales and settlements	(9)		0
Transfers from level 3 to level 2	0
Balance at end of period	23		21
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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1
Actual return on plan assets relating to assets still held at the reporting date	0
Actual return on plan assets relating to assets sold during the period	0
Purchases, sales and settlements	0
Transfers from level 3 to level 2	(1)
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	80		104
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	75		80
Actual return on plan assets relating to assets still held at the reporting date	3		19
Actual return on plan assets relating to assets sold during the period	0		0
Purchases, sales and settlements	2		5
Transfers from level 3 to level 2	0
Balance at end of period	80		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]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
LG And E And KU Energy LLC [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	37		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	42		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	(7)		(5)
Transfers from level 3 to level 2	0
Balance at end of period	37		33
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	0	[2]	(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0	[2]	(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	(115)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(115)		(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	4,156		4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	4,156		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	59.00%		51.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			52.00%	[1]
Target asset allocation - LKE Plans			52.00%	[1]
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	30.00%		26.00%	[1]
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	17.00%	[3]	13.00%	[1],[3]
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	12.00%		12.00%	[1]
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	39.00%		47.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			46.00%	[1]
Target asset allocation - LKE Plans			46.00%	[1]
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	40.00%	[3]	44.00%	[1],[3]
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	(1.00%)		3.00%	[1]
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%		2.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			2.00%	[1]
Target asset allocation - LKE Plans			2.00%	[1]
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			82		68
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			74		68
Balance at end of period			82		68
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]
2015			14
2016			14
2017			15
2018			16
2019			17
2020-2024			88
Expected Federal Subsidy (Details) [Abstract]
Federal subsidy 2015			0
Federal subsidy 2016			0
Federal subsidy 2017			1
Federal subsidy 2018			0
Federal subsidy 2019			0
Federal subsidy 2020-2024			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			13
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period			9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			12
Balance at end of period			9
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	12		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		9
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Money Market Funds [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	182		169
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	182		169
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	182		169
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	182		169
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Large Cap Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	100		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	100		136
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	100		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	100		136
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	36		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	36		33
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	36		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	36		33
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits United States [Member] | Municipalities Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
LG And E And KU Energy LLC [Member] | 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	[7]	1	[7]
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1	[7]	1	[7]
LG And E And KU Energy LLC [Member] | 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	115		136
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	115		136
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	330		347
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	330		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	12		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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	318		338
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	318		338
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
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
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			301		287
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			281		287
Balance at end of period			301		287
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]
2015			15
2016			16
2017			17
2018			18
2019			19
2020-2024			105
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	281		301
Undivided interest percentage in each asset category that PPL subsidiary holds	7.00%		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			55
Minimum number of days notice required to redeem shares for investments in hedge funds			65
Maximum number of days notice required to redeem shares for investments in hedge funds			95
Actual Allocation by Plan Asset (Details) [Abstract]
Percentage of trust assets	100.00%		100.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			100.00%	[1]
Target asset allocation - LKE Plans			100.00%	[1]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	4,271		4,809
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period			4,271
Balance at end of period	4,271		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	1,130		1,211
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	1,130		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	3,000		3,440
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	3,000		3,440
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	141		158
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	146		141
Actual return on plan assets relating to assets still held at the reporting date	5		18
Actual return on plan assets relating to assets sold during the period	5		(1)
Purchases, sales and settlements	(14)		0
Transfers from level 3 to level 2	(1)
Balance at end of period	141		158
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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	120		246
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	120		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	480		432
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	480		432
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]
Fair value at end of period	134		114
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		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]
Fair value at end of period	346		318
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	346		318
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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	137		145
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	137		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	749		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	749		818
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	13		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	13		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	736		818
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	736		818
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | United States Commingled Debt Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	630		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	630		615
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	163		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	163		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	467		615
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	467		615
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Equity Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	617		723
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	617		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]
Fair value at end of period	563		706
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	563		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]
Fair value at end of period	54		17
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	54		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	11		2
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	11		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]
Fair value at end of period	1		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1		1
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	0		0
Purchases, sales and settlements	0		0
Transfers from level 3 to level 2	0
Balance at end of period	1		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]
Fair value at end of period	963		1,109
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	963		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	940		1,088
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	940		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]
Fair value at end of period	23		21
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	27		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	5		(1)
Purchases, sales and settlements	(9)		0
Transfers from level 3 to level 2	0
Balance at end of period	23		21
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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	24		9
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	24		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	1
Actual return on plan assets relating to assets still held at the reporting date	0
Actual return on plan assets relating to assets sold during the period	0
Purchases, sales and settlements	0
Transfers from level 3 to level 2	(1)
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	7		8
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	7		8
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | International Debt Securities [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	108		90
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	108		90
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Commodities Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	134		148
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	134		148
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Real Estate Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
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]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	80		104
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Private Equity Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	80		104
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	75		80
Actual return on plan assets relating to assets still held at the reporting date	3		19
Actual return on plan assets relating to assets sold during the period	0		0
Purchases, sales and settlements	2		5
Transfers from level 3 to level 2	0
Balance at end of period	80		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]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	210		223
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	210		223
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Hedge Fund Of Funds Alternative Investments [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	12		12
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	12		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 1 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0		0
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 2 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	(49)		92
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(49)		92
Louisville Gas And Electric Co [Member] | Pension Benefits United States [Member] | Master Trust [Member] | Interest Rate Swaps Derivatives [Member] | Level 3 [Member]
Defined benefit plan fair value of plan assets (Details) [Abstract]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	37		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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	0		0
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	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]
Fair value at end of period	37		33
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at beginning of period	42		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	(7)		(5)
Transfers from level 3 to level 2	0
Balance at end of period	37		33
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	0	[2]	(41)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	0	[2]	(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	(115)		(136)
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	(115)		(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	4,156		4,632
Change in Fair Value of Level 3 Plan Assets [Roll Forward]
Balance at end of period	$ 4,156		$ 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	59.00%		51.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			52.00%	[1]
Target asset allocation - LKE Plans			52.00%	[1]
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	30.00%		26.00%	[1]
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	17.00%	[3]	13.00%	[1],[3]
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	12.00%		12.00%	[1]
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	39.00%		47.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			46.00%	[1]
Target asset allocation - LKE Plans			46.00%	[1]
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	40.00%	[3]	44.00%	[1],[3]
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	(1.00%)		3.00%	[1]
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%		2.00%	[1]
Target Allocations (Details ) [Abstract]
Target asset allocation, weighted average			2.00%	[1]
Target asset allocation - LKE Plans			2.00%	[1]

[1] Allocations exclude consideration of cash for the WKE Bargaining Employees' Retirement Plan and a group annuity contract held by the LG&E and KU Retirement Plan.

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

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

[4] Includes commingled debt funds.

[5] Includes money market funds.

[6] Includes commingled debt funds and debt securities.

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