Postretirement Benefits (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined contribution plans
Costs related to defined contribution plans	$ 90	$ 118	$ 362	$ 311
U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	68	97	298	247
Non-U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	$ 22	$ 21	$ 64	$ 64