v3.10.0.1
Equity (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($)
$ in Millions
Dec. 31, 2018
Dec. 31, 2017
Equity [Abstract]    
Unrealized gains (losses) on marketable securities $ 3 $ (43)
Deferred gains (losses) on cash flow hedges 55 9
Unrecognized gains (losses) on employee benefit obligations 325 260
Cumulative translation adjustments (751) 153
Accumulated other comprehensive income (loss), net of deferred taxes $ (368) $ 379