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Restructuring - Charges Related to Restructuring Program Activities by Type of Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 658 | $ 927 | $ 1,069
Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 21 | 138 | 181
Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 3 | 2 | 95
Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 2 | 11 | 142
Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 632 | 776 | 651
Separation Costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 473 | 552 | 216
Separation Costs | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Separation Costs | Selling, general 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 | 473 | 552 | 216
Accelerated Depreciation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | (1) | 60 | 227
Accelerated Depreciation | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 10 | 52 | 77
Accelerated Depreciation | Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 2 | 2 | 8
Accelerated Depreciation | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | (13) | 6 | 142
Accelerated Depreciation | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 0
Other |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 186 | 315 | 626
Other | Cost of sales |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 11 | 86 | 104
Other | Selling, general and administrative |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 1 | 0 | 87
Other | Research and development |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 15 | 5 | 0
Other | Restructuring costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 159 | $ 224 | $ 435

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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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
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