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Restructuring - Charges Activities by Type of Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | $ 868 | $ 880 | $ 915
Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 160 | 175 | 251
Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 19 | 47 | 34
Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 28 | 83 | 4
Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 661 | 575 | 626
Separation Costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 451 | 385 | 572
Separation Costs | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 0 | 0 | 0
Separation Costs | Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 0 | 0 | 0
Separation Costs | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 0 | 0 | 0
Separation Costs | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 451 | 385 | 572
Accelerated Depreciation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 91 | 268 | 233
Accelerated Depreciation | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 52 | 143 | 198
Accelerated Depreciation | Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 12 | 44 | 33
Accelerated Depreciation | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 27 | 81 | 2
Accelerated Depreciation | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 0 | 0 | 0
Other |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 326 | 227 | 110
Other | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 108 | 32 | 53
Other | Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 7 | 3 | 1
Other | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | 1 | 2 | 2
Other | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | $ 210 | $ 190 | $ 54

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