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Restructuring - Charges Related to Restructuring Program Activities by Type of Cost (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 104 | $ 215
Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 55 | 84
Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | (2) | 49
Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 51 | 82
Materials and production |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 6 | 63
Materials and production | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Materials and production | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 51
Materials and production | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 6 | 12
Marketing and administrative |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 1 | 1
Marketing and administrative | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 0
Marketing and administrative | Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 1 | 0
Marketing and administrative | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 1
Research and development |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 2 | 0
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 | (3) | (2)
Research and development | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 5 | 2
Restructuring costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 95 | 151
Restructuring costs | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 55 | 84
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 | $ 40 | $ 67

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- Definition Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + Details
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