v3.19.3.a.u2
Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Pension Plans Defined Benefit [Member] | U.S.      
Net periodic benefit cost of all defined benefit plans      
Service cost $ 79 $ 83 $ 89
Interest cost 79 99 118
Expected return on plan assets (74) (114) (132)
Amortization of prior service cost (credit) 0 0 4
Recognized net actuarial loss (gain) 54 53 69
Pension settlement losses 62 196 131
Net periodic benefit cost 200 317 279
Pension Plans Defined Benefit [Member] | Foreign Plan [Member]      
Net periodic benefit cost of all defined benefit plans      
Service cost 69 81 77
Interest cost 97 107 103
Expected return on plan assets (138) (155) (158)
Amortization of prior service cost (credit) (2) (5) (6)
Recognized net actuarial loss (gain) 32 31 50
Pension settlement losses 0 0 0
Net periodic benefit cost 58 59 66
Other Postretirement Benefit Plans, Defined Benefit [Member]      
Net periodic benefit cost of all defined benefit plans      
Service cost 1 1 2
Interest cost 8 8 9
Expected return on plan assets 0 0 0
Amortization of prior service cost (credit) (33) (35) (36)
Recognized net actuarial loss (gain) (2) (1) (3)
Pension settlement losses 0 0 0
Net periodic benefit cost $ (26) $ (27) $ (28)