Postretirement Benefits (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Contribution Plan
Costs related to defined contribution plans	$ 110	$ 125	$ 404	$ 313
U.S. Plans
Defined Contribution Plan
Costs related to defined contribution plans	81	103	321	248
Non-U.S. Plans
Defined Contribution Plan
Costs related to defined contribution plans	$ 29	$ 22	$ 83	$ 65