v3.21.2
Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2021
Mar. 31, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Pension Plans Defined Benefit [Member] | U.S.          
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]          
Service cost $ 18   $ 21 $ 39 $ 42
Interest cost 15   17 28 34
Expected return on plan assets (20)   (21) (44) (42)
Amortization of prior service cost (credit) 0   0 0 0
Recognized net actuarial (gain) loss 12   13 27 25
Settlements 42   0 44 1
Curtailments   $ 12   12 0
Special Termination Benefits       9 0
Net periodic benefit cost 67   30 115 60
Pension Plans Defined Benefit [Member] | Int'l (Pension Benefits) [Member]          
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]          
Service cost 16   13 31 27
Interest cost 20   20 40 42
Expected return on plan assets (30)   (34) (60) (71)
Amortization of prior service cost (credit) 0   0 0 0
Recognized net actuarial (gain) loss 8   5 16 11
Settlements 0   0 0 (1)
Curtailments       0 0
Special Termination Benefits       0 0
Net periodic benefit cost 14   4 27 8
Other Postretirement Benefit Plans, Defined Benefit [Member]          
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]          
Service cost 1   0 1 1
Interest cost 1   1 2 3
Expected return on plan assets 0   0 0 0
Amortization of prior service cost (credit) (10)   (8) (19) (16)
Recognized net actuarial (gain) loss 1   0 1 0
Settlements 0   0 0 0
Curtailments       0 0
Special Termination Benefits       0 0
Net periodic benefit cost $ (7)   $ (7) $ (15) $ (12)