Annual report [Section 13 and 15(d), not S-K Item 405]

MULTIEMPLOYER EMPLOYEE BENEFIT PLANS - Narrative (Details)

v3.25.4
MULTIEMPLOYER EMPLOYEE BENEFIT PLANS - Narrative (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
employee
Dec. 31, 2024
USD ($)
Dec. 31, 2023
Dec. 31, 2012
employee
Multiemployer Plans [Line Items]        
Number of employees under a national master agreement and various supplemental agreements with local unions affiliated with Teamster 295,000      
Number of employees under a collective bargaining agreement with the teamsters 10,000      
Number of pilots under a collective bargaining agreement with the Independent Pilots Association 3,400      
Ground mechanics employed under IAM agreements 2,000      
Employees not employed under agreement with teamsters 3,000      
Pension Benefits        
Multiemployer Plans [Line Items]        
Multiemployer pension plans, maximum term to forecast a funding deficiency in the orange zone 6 years      
Multiemployer plans, period contributions, significance of contributions 5.00% 5.00% 5.00%  
Debt instrument, term 37 years      
Multi-employer plans, fair value of withdrawal liability | $ $ 662 $ 651    
Pension Benefits | Other non-current liabilities        
Multiemployer Plans [Line Items]        
Multiemployer plans, present value of withdrawal liability | $ 795 804    
Pension Benefits | Other current liabilities        
Multiemployer Plans [Line Items]        
Multiemployer plans, present value of withdrawal liability | $ $ 9 $ 9    
Red Zone, Less than 65% Funded | Maximum | Pension Benefits        
Multiemployer Plans [Line Items]        
Multiemployer pension plans, percentage of plan funded 65.00%      
Otange Zone, Less than 80% and Have an Accumulated Funding Deficiency or Expect to Have a Deficiency Within Six Years | Pension Benefits        
Multiemployer Plans [Line Items]        
Multiemployer pension plans, percentage of plan funded 80.00%      
Yellow Zone, Less than 80% Funded | Maximum | Pension Benefits        
Multiemployer Plans [Line Items]        
Multiemployer pension plans, percentage of plan funded 80.00%      
Green Zone, At Least 80% Funded | Minimum | Pension Benefits        
Multiemployer Plans [Line Items]        
Multiemployer pension plans, percentage of plan funded 80.00%      
Represented by Teamsters        
Multiemployer Plans [Line Items]        
Number of employees under a national master agreement and various supplemental agreements with local unions affiliated with Teamster       10,200