Postretirement Benefits (Details 2) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Defined Contribution Plan
Costs related to defined contribution plans	$ 151	$ 42
U.S. Plans
Defined Contribution Plan
Costs related to defined contribution plans	125	19
Non-U.S. Plans
Defined Contribution Plan
Costs related to defined contribution plans	$ 26	$ 23