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Restructuring - Narrative (Details) - 2017 Plan $ in Millions | 3 Months Ended | 12 Months Ended | 24 Months Ended
--- | --- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2018 USD ($) job_elimination | Dec. 31, 2018 USD ($) job_elimination
Restructuring Cost and Reserve [Line Items] |  |  |
Additional expected cost | $ 200 | $ 200 | $ 200
Additional expected cash payments | 150 |  |
Additional expected con-cash charges | 50 |  |
Expected cost | 1,225 | 1,225 | $ 1,225
Number of positions eliminated | job_elimination |  |  | 4,366
Incurred restructuring cost |  | 485 | $ 982
Workforce reduction |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cost | 450 | 450 | 450
Incurred restructuring cost |  | 115 | 414
Technology rationalization |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cost | 130 | 130 | 130
Incurred restructuring cost |  | 47 | 80
Lease consolidation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cost | 65 | 65 | 65
Incurred restructuring cost |  | 28 | 36
Asset impairments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cost | 50 | 50 | 50
Incurred restructuring cost |  | 13 | 39
Other Restructuring |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cost | $ 530 | 530 | 530
Incurred restructuring cost |  | $ 282 | $ 413
Minimum |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected number of positions eliminated | job_elimination |  | 4,800 |
Maximum |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected number of positions eliminated | job_elimination |  | 5,400 |

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- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: 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 2: 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 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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