Cover Page - USD ($)
$ in Billions
 12 Months Ended
Dec. 31, 2019
Jan. 31, 2020
Jun. 30, 2019
Cover page.      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2019    
Document Transition Report false    
Entity File Number 001-5424    
Entity Registrant Name DELTA AIR LINES, INC.    
Entity Central Index Key 0000027904    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 58-0218548    
Entity Address, Address Line One Post Office Box 20706    
Entity Address, City or Town Atlanta    
Entity Address, State or Province GA    
Entity Address, Postal Zip Code 30320-6001    
City Area Code 404    
Local Phone Number 715-2600    
Title of 12(b) Security Common Stock, par value $0.0001 per share    
Trading Symbol DAL    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Public Float     $ 36.9
Entity Common Stock, Shares Outstanding   640,093,995  
Documents Incorporated by Reference Part III of this Form 10-K incorporates by reference certain information from the registrant's definitive Proxy Statement for its Annual Meeting of Stockholders to be filed with the Securities and Exchange Commission.