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Restructuring - Charges Activities by Type of Cost (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 168 | $ 187
Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 47 | 128
Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 53 | 34
Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 68 | 25
Cost of sales |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 68 | 34
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 | 25 | 34
Cost of sales | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 43 | 0
Selling, general and administrative |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 11 |
Selling, general and administrative | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 |
Selling, general and administrative | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 11 |
Selling, general and administrative | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 |
Research and development |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 17 |
Research and development | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 |
Research and development | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 17 |
Research and development | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 |
Restructuring costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 72 | 153
Restructuring costs | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 47 | 128
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 | $ 25 | $ 25

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