v3.3.1.900
Income Taxes Income Tax Rate Reconciliation (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended 36 Months Ended
Mar. 31, 2021
Mar. 31, 2016
Dec. 31, 2015
Mar. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Mar. 31, 2020
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]              
Notional U.S. federal income taxes at statutory rate     $ 527   $ 566 $ 513  
Income taxed at other rates     (207)   (286) (273)  
Change in valuation allowance     15   18 6  
Other change in tax reserves     8   (4) (13)  
Witholding taxes     57   57 48  
Tax credits     (133)   (89) (52)  
Change in tax law     11   0 15  
Other adjustments     (15)   (7) (4)  
Total income tax expense     $ 263   $ 255 $ 240  
Effective tax rate     17.00%   16.00% 16.00%  
Income Tax Reconciliation, Other Reconciling Items [Abstract]              
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate     35.00%        
Income Taxed at Other Rates Foreign Income Rate Differential in China, Turkey, and Honduras     $ 92   $ 67 $ 71  
Income Tax Holiday, Aggregate Dollar Amount     $ 16   $ 28 $ 23  
Income Tax Holiday, Income Tax Benefits Per Share     $ 0.06   $ 0.09 $ 0.07  
Research and Development Tax Credit           $ 19  
Her Majesty's Revenue and Customs (HMRC) | Foreign Tax Authority              
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]              
Change in tax law           $ 12  
Income Tax Reconciliation, Other Reconciling Items [Abstract]              
Corporate Income Tax Rate       21.00%   23.00%  
Subsequent Event | Her Majesty's Revenue and Customs (HMRC) | Foreign Tax Authority              
Income Tax Reconciliation, Other Reconciling Items [Abstract]              
Corporate Income Tax Rate 18.00% 20.00%         19.00%