v3.22.4
Pension and Other Postretirement Benefits - Narrative (Details)
$ in Millions
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Nov. 30, 2020
participant
Jul. 01, 2020
USD ($)
participant
May 31, 2020
participant
Apr. 30, 2021
USD ($)
plan
participant
Dec. 31, 2020
USD ($)
segment
participant
Jul. 31, 2020
USD ($)
Jun. 30, 2020
USD ($)
participant
Jun. 30, 2021
plan
participant
Jun. 30, 2020
USD ($)
Sep. 30, 2020
USD ($)
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Sep. 30, 2022
May 31, 2022
USD ($)
May 14, 2022
claimant
Aug. 31, 2021
USD ($)
Apr. 01, 2020
USD ($)
Jan. 01, 2020
USD ($)
Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Retirement plans, accumulated other comprehensive loss                                     $ 50    
Noncurrent assets                                     65    
Noncurrent liability                                     $ 15    
Weighted average duration of projected plan cash flows under yield curve model                       11 years                  
Cash contributions to pension plans                       $ 31 $ 458 $ 271              
Defined contribution plan, cost                       45 39 35              
Accrued pension benefits                       586 717                
Settlements related to employee retirement benefit plans                       (47) (584) (199)              
Labor Agreement, Number of Employees | claimant                                 3,300        
Labor Agreement, One Time Signing Bonus                       19                  
Forecast | Minimum                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Expected long-term rate of return on plan assets                     5.50%                    
Forecast | Maximum                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Expected long-term rate of return on plan assets                     6.50%                    
Funded                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Cash contributions to pension plans                       31 458 271              
U.S.                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Retirement plans, liability                                       $ 1,920  
Retirement plan, current liability                                       60  
Projected benefit obligation                                       4,255  
Retirement plans, plan asset                                       2,335  
Retirement plans, accumulated other comprehensive loss                                       $ 1,752  
Pension benefits​                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Retirement plan, current liability                       7 8                
Projected benefit obligation         $ 4,081             1,961 2,817 4,081              
Retirement plans, plan asset         $ 2,754             1,383 2,124 $ 2,754              
Noncurrent assets                       15 32                
Noncurrent liability                       586 717                
Settlement of plan obligations                       (78) (1,051)                
Contributions by employer                       $ 31 $ 458                
Defined benefit plan, discount rate                       5.49% 2.76%                
Expected long-term rate of return on plan assets                       5.18% 4.91% 6.09%              
Settlements related to employee retirement benefit plans                       $ (47) $ (584) $ (199)              
Pension benefits​ | Funded | Forecast                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Minimum required contribution to pension plans in 2021                     $ 38                    
Pension benefits​ | U.S.                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Projected benefit obligation       $ 3,337               1,716 2,398                
Retirement plans, plan asset       2,790               1,167 1,744                
Retirement plans, accumulated other comprehensive loss       $ (117)                                  
Defined benefit plan, number of participants | participant 30,000     8,400 7,000     23,000                          
Settlement of plan obligations       $ 995 $ 240                                
Defined benefit plan, plan assets, transfer of plan assets       1,007 $ 245                                
Contributions by employer       $ 250                                  
Defined benefit plan, discount rate       3.10% 2.54%                 2.54%              
Settlement charge         $ (140)               549                
Settlement charge, after-tax         $ 108               423                
Number of plans with obligations transferred to insurance company | segment         2                                
Number of defined benefit pension plans | plan       2       2                          
Accrued pension benefits       $ 152                                  
Settlements related to employee retirement benefit plans                         $ 549                
Pension benefits​ | U.S. | Hourly Plan                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Defined benefit plan, discount rate                         2.96%     4.66%          
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax                       10                  
Defined Benefit Plan, Net Periodic Benefit Cost, (Increase) Decrease for Remeasurement due to Amendment                               $ 8          
Defined Benefit Plan, Change in amounts for Asset (Liability) Recognized in Statement of Financial Position                               13          
Defined Benefit Plan, Service Cost, (Increase) Decrease for Remeasurement due to Amendment                               2          
Defined Benefit Plan, Non-service Cost, (Increase) Decrease for Remeasurement due to Amendment                               $ 10          
Pension benefits​ | U.S. | Salaried Plan                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Defined benefit plan, discount rate                         2.82%   5.71%            
Settlement charge                       15                  
Settlement charge, after-tax                       (12)                  
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax                       26                  
Defined Benefit Plan, Net Periodic Benefit Cost, (Increase) Decrease for Remeasurement due to Amendment                       8                  
Defined Benefit Plan, Change in amounts for Asset (Liability) Recognized in Statement of Financial Position                       34                  
Pension benefits​ | U.S. | Funded | Forecast                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Minimum required contribution to pension plans in 2021                     $ 31                    
Pension benefits​ | U.K.                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Projected benefit obligation   $ 240                                      
Retirement plans, plan asset   $ 260                                      
Defined benefit plan, number of participants | participant   1,050 3,350       1,800                            
Settlement of plan obligations             $ 400                            
Defined benefit plan, plan assets, transfer of plan assets             $ 460             $ 58              
Contributions by employer                 $ 10                        
Defined benefit plan, discount rate             1.55%   1.55%                       2.05%
Net reduction to remaining plan obligations due to remeasurement of plan                   $ 250                      
Settlement charge                           (58)              
Settlement charge, after-tax                           48              
Other postretirement benefits                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Retirement plan, current liability                       27 $ 29                
Projected benefit obligation         $ 514             329 440 514              
Retirement plans, plan asset         $ 0             0 0 0              
Noncurrent assets                       0 0                
Noncurrent liability                       302 411                
Settlement of plan obligations                       0 0                
Contributions by employer                       $ 0 $ 0                
Defined benefit plan, discount rate                       5.62% 2.90%                
Settlements related to employee retirement benefit plans                       $ 0 $ 0 $ 0              
Other postretirement benefits | U.S.                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Defined benefit plan, discount rate         2.61% 2.54%               2.61%       2.78%     3.17%
Net decrease to postretirement benefits liability           $ 7           $ 34                  
Net decrease to Accumulated other comprehensive loss (after-tax)           5                              
Decrease in estimated annual benefit payments beginning in 2021           $ 20                       $ (4)      
Health care cost trend rate assumed for next year                       6.30% 4.50%                
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax                       $ 26                  
Other postretirement benefits | U.S. | Forecast                                          
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                                          
Health care cost trend rate assumed for next year                     6.30%