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Restructuring - Schedule of Restructuring and Related Expense (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items] |
Estimated Remaining Costs | $ 528
2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 497
Expected cost | 1,025
Workforce reduction | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 299
Estimated Remaining Costs | 151
Expected cost | 450
Technology rationalization | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 33
Estimated Remaining Costs | 97
Expected cost | 130
Incurred contract termination costs | 1
Expected contract termination cost remaining | 10
Lease consolidation | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 8
Estimated Remaining Costs | 77
Expected cost | 85
Incurred contract termination costs | 8
Expected contract termination cost remaining | 80
Asset impairments | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 26
Estimated Remaining Costs | 24
Expected cost | 50
Other Restructuring | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
Incurred restructuring cost | 131
Estimated Remaining Costs | 179
Expected cost | 310
Incurred contract termination costs | 3
Expected contract termination cost remaining | $ 10

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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/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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- 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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