v3.25.4
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment, net (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Property, Plant and Equipment [Line Items]    
Less: accumulated depreciation and amortization $ (24,719) $ (23,228)
Total property and equipment, net 39,743 37,595
Flight equipment    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 47,981 44,722
Flight equipment | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 30 years  
Flight equipment | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 34 years  
Ground property and equipment    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 11,165 10,695
Ground property and equipment | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 3 years  
Ground property and equipment | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 40 years  
Information technology-related assets    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 3,167 3,135
Information technology-related assets | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 3 years  
Information technology-related assets | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 15 years  
Flight and ground equipment under finance leases    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 1,185 1,196
Less: accumulated depreciation and amortization (350) (371)
Advance payments for equipment    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 964 $ 1,075