v3.7.0.1
Post-Employment Benefits - General (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Defined Benefit Plans    
Defined benefit plan net periodic benefit cost    
Service cost - benefits earned during the period $ 72 $ 67
Interest cost on projected benefit obligations 72 73
Expected return on plan assets (152) (141)
Net amortization of:    
Actuarial loss, net 42 32
Net cost 34 31
Postemployment Obligations and Other Long Term Liabilities [Abstract]    
Company contributions 283 491
Medical and Dental Plans    
Defined benefit plan net periodic benefit cost    
Service cost - benefits earned during the period 7 7
Interest cost on projected benefit obligations 11 12
Expected return on plan assets (8) (9)
Net amortization of:    
Actuarial loss, net 6 6
Prior service cost (credit) (11) (11)
Net cost 5 5
Postemployment Obligations and Other Long Term Liabilities [Abstract]    
Company contributions 11 $ 9
AMO    
Postemployment Obligations and Other Long Term Liabilities [Abstract]    
Curtailment gain related to disposition of AMO $ 10