Pension and Other Postretirement Employee Benefit Plans - Pretax Amortization from AOCI (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Defined benefit pension plans, U.S.
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss/(gain)	$ 216
Prior service cost/(credit)	(34)
Total	182
Non-U.S. defined benefit pension plans
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss/(gain)	28
Prior service cost/(credit)	(2)
Total	26
OBEP plans, U.S.
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss/(gain)	0
Prior service cost/(credit)	0
Total	0
OPEB plans, Non-U.S.
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss/(gain)	0
Prior service cost/(credit)	0
Total	$ 0