Employee Benefits (Details Textual) $ in Millions	6 Months Ended
	Jun. 30, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Maximum annual increase percentage to company contribution for retiree medical coverage	4.00%
Contribution to other post retirement plans	$ 77
Defined benefit plan, expected contributions during the remaining of fiscal year	86
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, contributions by employer to employee pension plan	214
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position	950
Pension Benefits | United States
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, contributions by employer to employee pension plan	113
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position	700
Pension Benefits | International
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position	$ 250