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Restructuring Narrative (Details) - 2017 Plan $ in Millions | 3 Months Ended
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Mar. 31, 2017 USD ($) job_elimination
Restructuring Cost and Reserve [Line Items] |
Expected total cost | $ 750
Number of positions eliminated to date | job_elimination | 1,065
Costs incurred | $ 144
Workforce reduction |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | 207
Costs incurred | 103
Technology rationalization |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | 146
Costs incurred | 3
Lease consolidation |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | 176
Costs incurred | 3
Asset impairments |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | 40
Costs incurred | 13
Other Restructuring |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | 181
Costs incurred | 22
Non-cash charges for asset impairments and lease consolidations |
Restructuring Cost and Reserve [Line Items] |
Expected total cost | $ 50
Minimum |
Restructuring Cost and Reserve [Line Items] |
Expected number of positions eliminated | job_elimination | 1,600
Maximum |
Restructuring Cost and Reserve [Line Items] |
Expected number of positions eliminated | job_elimination | 1,900

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