v3.26.3
FAIR VALUE MEASUREMENTS - Securities Activity (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Purchases of Investments     $ 2,530 $ 2,407
I&M        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Purchases of Investments     2,493 2,387
Spent Nuclear Fuel and Decommissioning Trusts        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Proceeds from Investment Sales $ 1,226 $ 1,038 2,435 2,332
Purchases of Investments 1,244 1,057 2,493 2,387
Gross Realized Gains on Investment Sales 126 113 134 117
Gross Realized Losses on Investment Sales 23 1 30 4
Spent Nuclear Fuel and Decommissioning Trusts | I&M        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Proceeds from Investment Sales 1,226 1,038 2,435 2,332
Purchases of Investments 1,244 1,057 2,493 2,387
Gross Realized Gains on Investment Sales 126 113 134 117
Gross Realized Losses on Investment Sales $ 23 $ 1 $ 30 $ 4