XML 94 R78.htm IDEA: XBRL DOCUMENT v3.10.0.1
Income Taxes (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 21.00% 35.00%  
DEFERRED TAX LIABILITIES:      
Accelerated depreciation $ 3,395 $ 3,123  
Other 92 83  
Deferred Tax Liabilities, Gross 3,487 3,206  
DEFERRED TAX ASSETS:      
Deferred tax assets construction obligation 355 318  
Accrued employee benefits 329 301  
Rapid rewards loyalty liability 267 338  
Other 109 130  
Total deferred tax assets 1,060 1,087  
Total deferred tax liabilities 2,427 2,119  
CURRENT:      
Federal 338 904 $ 778
State 60 72 69
Total current 398 976 847
DEFERRED:      
Federal 299 200 393
State 2 2 27
Change in federal statutory rate 0 (1,270) 0
Total deferred 301 (1,068) 420
Total 699 (92) 1,267
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]      
Tax at statutory U.S. tax rates 664 1,143 1,208
State income taxes, net of federal benefit 49 50 62
Change in federal statutory rate 0 (1,270) 0
Other, net $ (14) $ (15) $ (3)