Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Estimated net loss to be amortized	$ 177
Estimated prior service cost to be amortized	13
Amounts charged to expense for defined contribution plans	56	$ 52	$ 62
Estimated contribution to pension plans	70
Net postemployment costs	$ 166	$ 187	167
Postemployment weighted-average discount rate	2.80%	3.50%
Postemployment annual weighted-average turnover rate	2.80%	2.70%
Postemployment percentage increase in assumed compensation cost	2.60%	2.20%
Assets related to postemployment cost	$ 25	$ 26
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	60.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	40.00%
Non-U.S. Plans - Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 7,555	7,157
Accumulated benefit obligations in excess of plan assets, projected obligation	6,529	6,355
Accumulated benefit obligations in excess of plan assets, accumulated benefit obligation	6,246	5,961
Accumulated benefit obligations in excess of plan assets, fair value of plan assets	4,712	4,766
Accrued postemployment costs	7,982	7,697	7,638
U.S. Plans - Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	376	360
Accumulated benefit obligations in excess of plan assets, projected obligation	405	389
Accumulated benefit obligations in excess of plan assets, accumulated benefit obligation	376	360
Accumulated benefit obligations in excess of plan assets, fair value of plan assets	297	298
Accrued postemployment costs	405	389	$ 438
Postemployment Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated net loss to be amortized	(67)
Accrued postemployment costs	$ 727	$ 745
Switzerland [Member] | Non-U.S. Plans - Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of foreign projected benefit obligation	60.00%	61.00%
Percentage of foreign plan assets	60.00%	60.00%