Postretirement Benefits (Details 2) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Defined contribution plans
Costs related to defined contribution plans	$ 96	$ 103
U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	80	85
Non-U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	$ 16	$ 18