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Restructuring - Charges Related to Restructuring Program Activities by Type of Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 927 | $ 1,069 | $ 1,110
Materials and production |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 138 | 181 | 361
Marketing and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 2 | 95 | 78
Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 11 | 142 | 52
Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 776 | 651 | 619
Separation Costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 552 | 216 | 208
Separation Costs | Materials and production |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Separation Costs | Marketing and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Separation Costs | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Separation Costs | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 552 | 216 | 208
Accelerated Depreciation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 60 | 227 | 174
Accelerated Depreciation | Materials and production |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 52 | 77 | 78
Accelerated Depreciation | Marketing and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 2 | 8 | 59
Accelerated Depreciation | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 6 | 142 | 37
Accelerated Depreciation | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Other |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 315 | 626 | 728
Other | Materials and production |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 86 | 104 | 283
Other | Marketing and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 87 | 19
Other | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 5 | 0 | 15
Other | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 224 | $ 435 | $ 411

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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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