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Restructuring - Charges Related to Restructuring Program Activities by Type of Cost (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 187 | $ 104
Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 128 | 55
Accelerated Depreciation |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 34 | (2)
Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 25 | 51
Cost of sales |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 34 | 6
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 | 34 | 0
Cost of sales | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 6
Selling, general and administrative |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 1
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 | 0 | 1
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 | 0 | 2
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 | 0 | (3)
Research and development | Other |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 0 | 5
Restructuring costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 153 | 95
Restructuring costs | Separation Costs |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | 128 | 55
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 | $ 40

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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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