XML 64 R40.htm IDEA: XBRL DOCUMENT v3.20.4
Significant Accounting Policies - Narrative (Details)
$ in Millions
 3 Months Ended 12 Months Ended
Apr. 01, 2020
Mar. 31, 2020
Dec. 31, 2020
USD ($)
plane
Sep. 30, 2020
USD ($)
Jun. 30, 2020
USD ($)
Mar. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Sep. 30, 2019
USD ($)
Jun. 30, 2019
USD ($)
Mar. 31, 2019
USD ($)
Dec. 31, 2020
USD ($)
plane
segment
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Jan. 01, 2020
USD ($)
Summary Of Significant Accounting Policies [Line Items]                              
Expiration period for refundable tickets                     1 year        
Extended expiration period for refundable tickets                     24 months        
Percent of ETCs and FFCs with expiration dates extending beyond 12 months     74.00%               74.00%        
Number of operating segments | segment                     1        
Revenue     $ 3,412 $ 2,489 $ 1,475 $ 7,979 $ 10,888 $ 11,380 $ 11,402 $ 9,589 $ 15,355 $ 43,259 $ 41,303    
Excise taxes refunded to customers but still outstanding from the U.S. government     150               $ 150        
Period over which miles are expected to be redeemed                     two years        
Cash collateral for a standby letter of credit     217               $ 217        
Amounts to be used for the payment of fees, principal and interest     6,800               6,800        
Carrying value of computer software     548       422       548 422      
Amortization expense                     55 60 67    
Projected amortization expense in 2021     50               50        
Projected amortization expense in 2022     40               40        
Projected amortization expense in 2023     37               37        
Projected amortization expense in 2024     32               32        
Projected amortization expense in 2025     28               28        
Advertising expense                     $ 87 $ 212 211    
Accounting Standards Update [Extensible List]                     us-gaap:AccountingStandardsUpdate201613Member us-gaap:AccountingStandardsUpdate201613Member [1]   us-gaap:AccountingStandardsUpdate201601Member  
Stockholders' equity     $ 5,960       11,531       $ 5,960 $ 11,531 10,042 $ 8,788  
Boeing 757-200                              
Summary Of Significant Accounting Policies [Line Items]                              
Number of planes permanently grounded | plane     11               11        
Tangible asset impairment charges     $ 94                        
Retained Earnings                              
Summary Of Significant Accounting Policies [Line Items]                              
Stockholders' equity     2,626       9,716       $ 2,626 9,716 6,715 4,603  
Adoption of New Accounting Standard                              
Summary Of Significant Accounting Policies [Line Items]                              
Stockholders' equity             (17) [1]         (17) [1]   0  
Adoption of New Accounting Standard | Retained Earnings                              
Summary Of Significant Accounting Policies [Line Items]                              
Stockholders' equity             $ (17) [1]         (17) [1]   $ (6) $ (17)
Minimum                              
Summary Of Significant Accounting Policies [Line Items]                              
Frequent flier program expiration period                     1 year        
Maximum                              
Summary Of Significant Accounting Policies [Line Items]                              
Frequent flier program expiration period                     9 years        
Computer software                              
Summary Of Significant Accounting Policies [Line Items]                              
Depreciation expense                     $ 172 135 122    
Advance Ticket Sales                              
Summary Of Significant Accounting Policies [Line Items]                              
Expiration period for advance ticket sales 24 months 12 months                          
Contract liabilities     $ 3,100               3,100        
Revenue recognized                     3,000 3,400 3,100    
Ancillary Fees Recorded within Passenger Revenues                              
Summary Of Significant Accounting Policies [Line Items]                              
Revenue                     918 2,400 2,200    
Other Operating Revenue                              
Summary Of Significant Accounting Policies [Line Items]                              
Revenue                     1,902 2,455 2,360    
Other Operating Revenue | Chase and Other Partner Agreements                              
Summary Of Significant Accounting Policies [Line Items]                              
Revenue                     $ 1,700 $ 2,000 2,000    
One-time payment                         $ 50    
[1] Transition adjustment due to the adoption of Accounting Standards Update No. 2016-13, Financial Instruments—Credit Losses.