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Utility Rate Regulation (Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 12 | $ 59 | $ (42)
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps |  | $ 2 | (9) | (101)
Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory asset and liability balances expected to be amortized into net periodic defined benefit costs in the next year |  | $ 68 |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period to be recorded as a regulatory asset in the following year |  | $ 16 |  |
Unamortized Loss On Debt [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2044 |  |
Power Purchase Agreement Ohio Valley Electric Corporation [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Mar. 31, 2026 |  |
Tax Cuts And Jobs Act [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 2,185 |  |
PPL Electric [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
Regulatory Assets and Liabilities - Storm Costs (Numeric) [Abstract] |  |  |  |
Period over which storm costs will be recovered (in years) |  | 3 years |  |
PPL Electric [Member] | Accumulated Cost Of Removal Of Utility Plant [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
PPL Electric [Member] | Storm Damage Expense Rider [Member] |  |  |  |
Regulatory Assets and Liabilities - Storm Damage Expense Rider (Numeric) [Abstract] |  |  |  |
Maximum reportable storm damage expenses to be recovered annually through base rates |  | $ 15 |  |
Amount of amortized storm expense included in base rate component |  | 5 |  |
PPL Electric [Member] | Act 129 Compliance Rider [Member] |  |  |  |
Regulatory Assets and Liabilities - Act 129 Compliance Rider (Numeric) [Abstract] |  |  |  |
Maximum recoverable cost |  | 250 |  |
Maximum recoverable cost Phase II |  | $ 185 |  |
Period over which program costs can be recovered for Phase II (in years) |  | 3 years |  |
Maximum amount of costs that can be recovered under the Act 129 Phase III plan |  | $ 313 |  |
Period over which program costs can be recovered for Phase III (in years) |  | 5 years |  |
LKE [Member] | Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period |  | $ 33 | 20 |
LGE [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
LGE [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
LGE [Member] | Interest Rate Swaps [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2033 |  |
LGE [Member] | Terminated Interest Rate Swap [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps | $ 9 |  |  |
LGE [Member] | Gas Line Tracker [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Gas Line Tracker (Numeric) [Abstract] |  |  |  |
Term, in years, of the gas service rider program |  | 5 years |  |
LGE [Member] | Gas Supply Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
LGE [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
KU [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
KU [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
KU [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
PPL Electric Utilities Corp [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 5 | 62 | (35)
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
Regulatory Assets and Liabilities - Act 129 Compliance Rider (Numeric) [Abstract] |  |  |  |
Maximum amount of costs that can be recovered under the Act 129 Phase III plan |  | $ 313 |  |
Period over which program costs can be recovered for Phase III (in years) |  | 5 years |  |
PPL Electric Utilities Corp [Member] | Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory asset and liability balances expected to be amortized into net periodic defined benefit costs in the next year |  | $ 30 |  |
PPL Electric Utilities Corp [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
Regulatory Assets and Liabilities - Storm Costs (Numeric) [Abstract] |  |  |  |
Period over which storm costs will be recovered (in years) |  | 3 years |  |
PPL Electric Utilities Corp [Member] | Unamortized Loss On Debt [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2029 |  |
PPL Electric Utilities Corp [Member] | Accumulated Cost Of Removal Of Utility Plant [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 5 years |  |
PPL Electric Utilities Corp [Member] | Storm Damage Expense Rider [Member] |  |  |  |
Regulatory Assets and Liabilities - Storm Damage Expense Rider (Numeric) [Abstract] |  |  |  |
Maximum reportable storm damage expenses to be recovered annually through base rates |  | $ 15 |  |
Amount of amortized storm expense included in base rate component |  | 5 |  |
PPL Electric Utilities Corp [Member] | Act 129 Compliance Rider [Member] |  |  |  |
Regulatory Assets and Liabilities - Act 129 Compliance Rider (Numeric) [Abstract] |  |  |  |
Maximum recoverable cost |  | 250 |  |
Maximum recoverable cost Phase II |  | $ 185 |  |
Period over which program costs can be recovered for Phase II (in years) |  | 3 years |  |
Maximum amount of costs that can be recovered under the Act 129 Phase III plan |  | $ 313 |  |
Period over which program costs can be recovered for Phase III (in years) |  | 5 years |  |
PPL Electric Utilities Corp [Member] | Tax Cuts And Jobs Act [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 1,019 |  |
LG And E And KU Energy LLC [Member] |  |  |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps |  | $ 0 | (9) | (88)
LG And E And KU Energy LLC [Member] | Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory asset and liability balances expected to be amortized into net periodic defined benefit costs in the next year |  | $ 38 |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period |  | $ 33 | 20 |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period to be recorded as a regulatory asset in the following year |  | $ 16 |  |
LG And E And KU Energy LLC [Member] | Unamortized Loss On Debt [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2044 |  |
LG And E And KU Energy LLC [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Mar. 31, 2026 |  |
LG And E And KU Energy LLC [Member] | Tax Cuts And Jobs Act [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 1,166 |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Interest Rate Swaps [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2033 |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Terminated Interest Rate Swap [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps | (9) |  |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Gas Line Tracker [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Gas Line Tracker (Numeric) [Abstract] |  |  |  |
Term, in years, of the gas service rider program |  | 5 years |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Gas Supply Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
LG And E And KU Energy LLC [Member] | KU [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
LG And E And KU Energy LLC [Member] | KU [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Louisville Gas And Electric Co [Member] |  |  |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps |  | $ 0 | (9) | (44)
Louisville Gas And Electric Co [Member] | Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory asset and liability balances expected to be amortized into net periodic defined benefit costs in the next year |  | $ 26 |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period |  | $ 18 | 11 |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period to be recorded as a regulatory asset in the following year |  | $ 10 |  |
Louisville Gas And Electric Co [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
Louisville Gas And Electric Co [Member] | Unamortized Loss On Debt [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2044 |  |
Louisville Gas And Electric Co [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Louisville Gas And Electric Co [Member] | Interest Rate Swaps [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2033 |  |
Louisville Gas And Electric Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Mar. 31, 2026 |  |
Louisville Gas And Electric Co [Member] | Terminated Interest Rate Swap [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 17 years |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps | $ 9 |  |  |
Louisville Gas And Electric Co [Member] | Gas Line Tracker [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Gas Line Tracker (Numeric) [Abstract] |  |  |  |
Term, in years, of the gas service rider program |  | 5 years |  |
Louisville Gas And Electric Co [Member] | Gas Supply Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 18 months |  |
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Louisville Gas And Electric Co [Member] | Tax Cuts And Jobs Act [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 532 |  |
Kentucky Utilities Co [Member] |  |  |  |
Regulatory Assets and Liabilities - Interest Rate Swaps (Numeric) [Abstract] |  |  |  |
Net cash settlements on terminated interest rate swaps |  | $ 0 | 0 | $ (44)
Kentucky Utilities Co [Member] | Defined Benefit Plans [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory asset and liability balances expected to be amortized into net periodic defined benefit costs in the next year |  | $ 12 |  |
Regulatory Asset Amortization Period |  | 15 years |  |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period |  | $ 15 | $ 9 |
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period to be recorded as a regulatory asset in the following year |  | $ 6 |  |
Kentucky Utilities Co [Member] | Storm Costs [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2020 |  |
Kentucky Utilities Co [Member] | Unamortized Loss On Debt [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Dec. 31, 2042 |  |
Kentucky Utilities Co [Member] | Fuel Adjustment Clause [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Kentucky Utilities Co [Member] | Power Purchase Agreement Ohio Valley Electric Corporation [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Amortization end date |  | Mar. 31, 2026 |  |
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Return on equity |  | 9.70% |  |
Regulatory Assets and Liabilities - Defined Benefit Plans (Numeric) [Abstract] |  |  |  |
Regulatory Asset Amortization Period |  | 12 months |  |
Regulatory Assets and Liabilities - Environmental Cost Recovery (Numeric) [Abstract] |  |  |  |
Return on equity |  | 9.70% |  |
Kentucky Utilities Co [Member] | Tax Cuts And Jobs Act [Member] |  |  |  |
Regulatory Assets and Liabilities (Numeric) [Line Items] |  |  |  |
Increase (Decrease) in Regulatory Assets and Liabilities |  | $ 634 |  |

X
- Definition The maximum amount of costs that can be recovered from June 1, 2016 through May 31, 2021 under the Act 129 Phase III Plan. + References No definition available. + Details
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X
- Definition The period over which Act 129 Phase II Plan costs will be recovered in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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X
- Definition The period over which Act 129 Phase III Plan costs will be recovered in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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X
- Definition Amount of deferred recovery of the difference between the pension cost calculated in accordance with the entities pension accounting policy and pension cost using a 15 year amortization period for actuarial gains and losses. + References No definition available. + Details
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X
- Definition Amount of deferred recovery of the difference between the pension cost calculated in accordance with the entities pension accounting policy and pension cost using a 15 year amortization period for actuarial gains and losses as provided in the June 30, 2015 rate case settlement expected to be recorded as a regulatory asset during the next twelve months period following the latest fiscal period. + References No definition available. + Details
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- Definition The maximum amount of recoverable costs under rate making rules. + References No definition available. + Details
Name: | ppl_MaximumRecoverableCost
Namespace Prefix: | ppl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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X
- Definition The maximum amount of recoverable costs under rate making rules for Phase II. + References No definition available. + Details
Name: | ppl_MaximumRecoverableCostPhase2
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- Definition The cash outflow for a financial contract that meets the hedge criteria as either a cash flow hedge, fair value hedge, or hedge of a net investment in a foreign operation. + References No definition available. + Details
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