Postretirement Benefits (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Defined contribution plans
Costs related to defined contribution plans	$ 50	$ 83	$ 246	$ 294
U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	31	62	188	232
Non-U.S. Plans
Defined contribution plans
Costs related to defined contribution plans	$ 19	$ 21	$ 58	$ 62