Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Estimated annual effective tax rate (as a percent)	31.00%	26.00%
Income tax (expense) benefit reported discretely in the period and excluded from the estimated annual effective tax rate	$ (43)
Tax benefit for settlement of stock-based compensation awards	8	$ 23
Tax benefit arising from calculation of the mandatory deemed repatriation of non-U.S. earnings		178
Tax Year Prior Years
Income Tax Contingency
Income tax examination, proposed liability increase/(decrease)	2,300
Foreign Plan
Income Tax Disclosure [Abstract]
Gain on remeasurement of a non-U.S. pension obligation	$ 254	$ 0