v3.25.4
EMPLOYEE BENEFIT PLANS - Benefit Plan Assets Measured at Fair Value on Recurring Basis (Details) - Recurring - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Benefit plan assets by asset class    
Benefit plan assets $ 17,281 $ 15,672
Level 1 and Level 2    
Benefit plan assets by asset class    
Benefit plan assets 4,236 3,234
Level 1 and Level 2 | Fixed income and fixed income-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 1,333 1,165
Level 1 and Level 2 | Cash equivalents    
Benefit plan assets by asset class    
Benefit plan assets 784 468
Level 1 and Level 2 | Equities and equity-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 1,372 981
Level 1 and Level 2 | Delta common stock    
Benefit plan assets by asset class    
Benefit plan assets 570 595
Level 1 and Level 2 | Real assets    
Benefit plan assets by asset class    
Benefit plan assets 177 25
Level 1    
Benefit plan assets by asset class    
Benefit plan assets 2,524 1,988
Level 1 | Fixed income and fixed income-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 78 85
Level 1 | Cash equivalents    
Benefit plan assets by asset class    
Benefit plan assets 494 330
Level 1 | Equities and equity-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 1,365 978
Level 1 | Delta common stock    
Benefit plan assets by asset class    
Benefit plan assets 570 595
Level 1 | Real assets    
Benefit plan assets by asset class    
Benefit plan assets 17 0
Level 2    
Benefit plan assets by asset class    
Benefit plan assets 1,712 1,246
Level 2 | Fixed income and fixed income-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 1,255 1,080
Level 2 | Cash equivalents    
Benefit plan assets by asset class    
Benefit plan assets 290 138
Level 2 | Equities and equity-related instruments    
Benefit plan assets by asset class    
Benefit plan assets 7 3
Level 2 | Delta common stock    
Benefit plan assets by asset class    
Benefit plan assets 0 0
Level 2 | Real assets    
Benefit plan assets by asset class    
Benefit plan assets 160 25
NAV    
Benefit plan assets by asset class    
Benefit plan assets $ 13,045 $ 12,438