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Utility Rate Regulation (Regulatory Matters) (Details)
 1 Months Ended 12 Months Ended
Feb. 16, 2026
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Nov. 26, 2025
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Oct. 20, 2025
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Sep. 30, 2025
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May 30, 2025
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Feb. 28, 2025
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Nov. 06, 2023
Oct. 16, 2018
Oct. 16, 2014
Dec. 31, 2025
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Mar. 31, 2025
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Dec. 31, 2022
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Dec. 31, 2025
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Nov. 24, 2025
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Jun. 13, 2025
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Mar. 13, 2025
Feb. 24, 2025
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Dec. 31, 2024
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Apr. 26, 2024
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   $ 2,092,000,000     $ 2,092,000,000         $ 2,060,000,000  
2025 CPCN Aggregate Projected Capital Expenditures           $ 3,700,000,000                          
Cane Run BESS                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN Aggregate Projected Capital Expenditures 2026-2031           775,000,000                          
Mill Creek NGCC                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN Aggregate Projected Capital Expenditures 2026-2031           $ 1,400,000,000                          
Storm Costs [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   113,000,000     113,000,000         113,000,000  
Other [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   $ 32,000,000     $ 32,000,000         46,000,000  
Kentucky Public Service Commission [Member] | Electric And Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 391,000,000                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 235,000,000                                
Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Electric And Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 233,000,000                                    
PPL Electric [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Distribution System Improvement Charge Cap           5.00%       5.00%     5.00%     7.50%      
PPL Electric [Member] | Pennsylvania Public Utility Commission [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Requested Distribution System Improvement Charge Cap                                     9.00%
PPL Electric [Member] | Pennsylvania Public Utility Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing       $ 356,000,000                              
Public Utilities, Requested Rate Increase (Decrease), Percentage       8.60%                              
Requested return on equity       11.30%                              
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amount Already Included In Customer Bills       $ 50,000,000                              
LGE [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN NGCC Combustion Turbine Facilities, Power | MW                       645              
CPCN NGCC Generation Unit | MW           645                          
CPCN Battery Storage Facility | MW           1,600                          
LGE [Member] | Mill Creek Unit 2                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Property, Plant and Equipment, Generation or Processing                   $ 199,000,000     $ 199,000,000            
LGE [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity                         9.35%            
Requested return on equity         10.95%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Return on Equity, Amended, Percentage     9.90%                                
LGE [Member] | Kentucky Public Service Commission [Member] | Mill Creek Unit 1 Retirement                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Costs Approved to be Recovered under Retired Asset Recovery Rider                                 $ 125,000,000    
LGE [Member] | Kentucky Public Service Commission [Member] | January 2025 KY Storm                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Regulatory Costs Not yet Approved                   $ 2,000,000     $ 2,000,000            
LGE [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Amortization period for the deferred recovery of a regulatory asset                   12 months     12 months            
LGE [Member] | Kentucky Public Service Commission [Member] | Minimum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     9.40%                                
LGE [Member] | Kentucky Public Service Commission [Member] | Maximum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     10.15%                                
LGE [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 60,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         14.00%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 45,000,000                                
LGE [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 105,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         8.30%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 58,000,000                                
LGE [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity 9.775%                                    
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Approved Return on Equity for Capital Rate Adjustment Mechanism, Percentage 9.675%                                    
LGE [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 46,000,000                                    
LGE [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 59,000,000                                    
KU [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN NGCC Combustion Turbine Facilities, Power | MW                       645              
CPCN NGCC Generation Unit | MW           645                          
KU [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity                         9.35%            
Requested return on equity         10.95%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Return on Equity, Amended, Percentage     9.90%                                
KU [Member] | Kentucky Public Service Commission [Member] | January 2025 KY Storm                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Regulatory Costs Not yet Approved                   $ 7,000,000     $ 7,000,000            
KU [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Amortization period for the deferred recovery of a regulatory asset                   12 months     12 months            
KU [Member] | Kentucky Public Service Commission [Member] | Minimum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     9.40%                                
KU [Member] | Kentucky Public Service Commission [Member] | Maximum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     10.15%                                
KU [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 226,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         11.50%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 132,000,000                                
KU [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity 9.775%                                    
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Approved Return on Equity for Capital Rate Adjustment Mechanism, Percentage 9.675%                                    
KU [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 128,000,000                                    
Rhode Island Energy                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Transfer from the Storm Fund Balance the RIPUC Directed                           $ 11,000,000          
Net Present Value of Hold Harmless Obligation                             $ 155,000,000        
Amount of Hold Harmless Obligation to be Credited to Customers in 2026                             74,000,000        
Amount of Hold Harmless Obligation to be Credited to Customers in 2027                             $ 81,000,000        
Winter Bill Credit Approved By the RIPUC                           $ 23.54          
Rhode Island Energy | Federal Energy Regulatory Commission                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Initial minimum base ROE to be reset by the FERC                 11.14%                    
Minimum base ROE reset by FERC                 10.57%                    
New ROE proposed by NETO and approved by FERC               10.41%                      
Rhode Island Energy | Federal Energy Regulatory Commission | Maximum ROE authorized                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity                 11.74%                    
Rhode Island Energy | Rhode Island Public Uitilty Commsion                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Requested return on equity   10.75%                                  
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Approved Spend on FY 2026 Gas ISR Plan                     $ 165,000,000                
Total Spend on FY 2027 Gas ISR Plan                   $ 184,000,000                  
Capital Investment Spend on FY 2027 Electric ISR Plan                   154,000,000                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | AMF Capital Investment                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Capital Investment Spend on FY 2027 Electric ISR Plan                   18,000,000                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Vegetation Management                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Spend on FY 2027 Electric ISR Plan                   13,000,000                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Capital Investment                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Spend on FY 2027 Gas ISR Plan                   166,000,000                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Paving Costs                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Spend on FY 2027 Gas ISR Plan                   17,000,000                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Paving Costs                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Approved Spend on FY 2026 Gas ISR Plan                     18,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Capital Investment                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Total Approved Spend on FY 2026 Gas ISR Plan                     147,000,000                
Approved Contingency Plan Spend on FY 2026 Gas ISR Plan                     15,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | AMF Capital Investment                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Approved Capital Investment Spend on FY 2026 Electric ISR Plan                     88,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Vegetation Management                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Approved Capital Investment Spend on FY 2026 Electric ISR Plan                     14,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Other O&M                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Approved Capital Investment Spend on FY 2026 Electric ISR Plan                     1,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Capital Investment                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Approved Capital Investment Spend on FY 2026 Electric ISR Plan                     $ 219,000,000                
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Gas Rates [Member] | Year 1                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   $ 115,000,000                                  
Public Utilities, Requested Rate Increase (Decrease), Percentage   36.40%                                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Gas Rates [Member] | Year 2                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   $ 32,000,000                                  
Public Utilities, Requested Rate Increase (Decrease), Percentage   7.40%                                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Electric And Gas Rates [Member] | Year 1                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   $ 181,000,000                                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Electric And Gas Rates [Member] | Year 2                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   49,000,000                                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Electric Rates [Member] | Year 1                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   $ 66,000,000                                  
Public Utilities, Requested Rate Increase (Decrease), Percentage   18.20%                                  
Rhode Island Energy | Rhode Island Public Uitilty Commsion | Electric Rates [Member] | Year 2                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing   $ 17,000,000                                  
Public Utilities, Requested Rate Increase (Decrease), Percentage   3.60%                                  
PPL Electric Utilities Corp [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   $ 725,000,000     $ 725,000,000         673,000,000  
Distribution System Improvement Charge Cap           5.00%       5.00%     5.00%     7.50%      
PPL Electric Utilities Corp [Member] | Storm Costs [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   $ 42,000,000     $ 42,000,000         22,000,000  
PPL Electric Utilities Corp [Member] | Other [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   2,000,000     2,000,000         2,000,000  
PPL Electric Utilities Corp [Member] | Pennsylvania Public Utility Commission [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Requested Distribution System Improvement Charge Cap                                     9.00%
PPL Electric Utilities Corp [Member] | Pennsylvania Public Utility Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing       $ 356,000,000                              
Public Utilities, Requested Rate Increase (Decrease), Percentage       8.60%                              
Requested return on equity       11.30%                              
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amount Already Included In Customer Bills       $ 50,000,000                              
Louisville Gas And Electric Co [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN NGCC Combustion Turbine Facilities, Power | MW                       645              
New NGCC LG&E Planned Ownership Percentage             0.31                        
Regulatory assets                   482,000,000     482,000,000         491,000,000  
CPCN NGCC Generation Unit | MW           645                          
BESS LG&E Planned Ownership Percentage           32.00%                          
CPCN Battery Storage Facility | MW           1,600                          
Louisville Gas And Electric Co [Member] | Mill Creek Unit 2                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Property, Plant and Equipment, Generation or Processing                   199,000,000     199,000,000            
Louisville Gas And Electric Co [Member] | Storm Costs [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   24,000,000     24,000,000         20,000,000  
Louisville Gas And Electric Co [Member] | Other [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   6,000,000     $ 6,000,000         4,000,000  
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity                         9.35%            
Requested return on equity         10.95%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Return on Equity, Amended, Percentage     9.90%                                
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Mill Creek Unit 1 Retirement                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Costs Approved to be Recovered under Retired Asset Recovery Rider                                 $ 125,000,000    
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | January 2025 KY Storm                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Regulatory Costs Not yet Approved                   $ 2,000,000     $ 2,000,000            
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Amortization period for the deferred recovery of a regulatory asset                   12 months     12 months            
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Minimum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     9.40%                                
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Maximum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     10.15%                                
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 60,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         14.00%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 45,000,000                                
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 105,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         8.30%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 58,000,000                                
Louisville Gas And Electric Co [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity 9.775%                                    
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Approved Return on Equity for Capital Rate Adjustment Mechanism, Percentage 9.675%                                    
Louisville Gas And Electric Co [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 46,000,000                                    
Louisville Gas And Electric Co [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 59,000,000                                    
Kentucky Utilities Co [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
CPCN NGCC Combustion Turbine Facilities, Power | MW                       645              
New NGCC KU Planned Ownership Percentage             0.69                        
Regulatory assets                   $ 467,000,000     $ 467,000,000         458,000,000  
CPCN NGCC Generation Unit | MW           645                          
BESS KU Planned Ownership Percentage           68.00%                          
Kentucky Utilities Co [Member] | Storm Costs [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   38,000,000     38,000,000         29,000,000  
Kentucky Utilities Co [Member] | Other [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Regulatory assets                   11,000,000     $ 11,000,000         $ 8,000,000  
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity                         9.35%            
Requested return on equity         10.95%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Return on Equity, Amended, Percentage     9.90%                                
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | January 2025 KY Storm                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Amount of Regulatory Costs Not yet Approved                   $ 7,000,000     $ 7,000,000            
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Environmental Cost Recovery [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Amortization period for the deferred recovery of a regulatory asset                   12 months     12 months            
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Minimum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     9.40%                                
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Maximum [Member]                                      
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage     10.15%                                
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Dollar amount requested increase in base rates with anticipated rate case filing         $ 226,000,000                            
Public Utilities, Requested Rate Increase (Decrease), Percentage         11.50%                            
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount     $ 132,000,000                                
Kentucky Utilities Co [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Return on equity 9.775%                                    
Regulatory Matters Federal Matters Federal Energy Regulatory Commission Wholesale Formula Rates Numeric [Abstract]                                      
Public Utilities, Approved Return on Equity for Capital Rate Adjustment Mechanism, Percentage 9.675%                                    
Kentucky Utilities Co [Member] | Subsequent Event [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]                                      
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]                                      
Public Utilities, Approved Rate Increase (Decrease), Amount $ 128,000,000