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Restructuring - Charges Activities by Type of Cost (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 335 | $ 168
Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 229 | 47
Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 20 | 53
Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 86 | 68
Cost of sales |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 27 | 68
Cost of sales | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Cost of sales | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 10 | 25
Cost of sales | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 17 | 43
Selling, general and administrative |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 3 | 11
Selling, general and administrative | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Selling, general and administrative | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 3 | 11
Selling, general and administrative | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Research and development |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 7 | 17
Research and development | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Research and development | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 7 | 17
Research and development | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Restructuring costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 298 | 72
Restructuring costs | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 229 | 47
Restructuring costs | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Restructuring costs | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 69 | $ 25

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