v3.20.4
Pension and Postretirement Benefit Plans and Defined Contribution Plans - Funded Status Recognized in Consolidated Balance Sheets (Details) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Postretirement Benefits Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Noncurrent assets [1] $ 0 $ 0
Current liabilities [2] (6) (24)
Noncurrent liabilities [3] (645) (1,124)
Funded status (651) (1,148)
US [Member] | Pension Plan [Member] | Qualified Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Noncurrent assets [1] 0 0
Current liabilities [2] 0 0
Noncurrent liabilities [3] (845) (1,949)
Funded status (845) (1,949)
US [Member] | U.S. Supplemental (Non-Qualified) Pension Plans [Member] | Non-Qualified Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Noncurrent assets [1] 0 0
Current liabilities [2] (127) (189)
Noncurrent liabilities [3] (1,239) (1,162)
Funded status (1,366) (1,351)
International [Member] | Pension Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Noncurrent assets [1] 522 453
Current liabilities [2] (31) (30)
Noncurrent liabilities [3] (2,681) (2,526)
Funded status $ (2,191) $ (2,103)
[1] Included in Other noncurrent assets.
[2] Included in Accrued compensation and related items.
[3] Included in Pension benefit obligations, Postretirement benefit obligations, and Other noncurrent liabilities, as appropriate.