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Restructuring - Schedule of Restructuring and Related Expenses (Details) - 2017 Plan $ in Millions | 3 Months Ended | 6 Months Ended | 30 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2019 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | $ 127 | $ 218 | $ 1,200
Estimated Remaining Costs | 150 | 150 | 150
Expected total cost | 1,350 | 1,350 | 1,350
Expected non-cash expense | 100 | 100 | 100
Workforce reduction |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | 78 | 102 | 516
Estimated Remaining Costs | 14 | 14 | 14
Expected total cost | 530 | 530 | 530
Technology rationalization |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | 4 | 15 | 95
Estimated Remaining Costs | 35 | 35 | 35
Expected total cost | 130 | 130 | 130
Contract termination costs incurred | 2 | 3 | 9
Expected contract termination cost remaining | 15 | 15 | 15
Lease consolidation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | 5 | 14 | 50
Estimated Remaining Costs | 30 | 30 | 30
Expected total cost | 80 | 80 | 80
Contract termination costs incurred | 4 | 13 | 46
Expected contract termination cost remaining | 80 | 80 | 80
Asset impairments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | 2 | 2 | 41
Estimated Remaining Costs | 4 | 4 | 4
Expected total cost | 45 | 45 | 45
Other costs associated with restructuring and separation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Costs incurred | 38 | 85 | 498
Estimated Remaining Costs | 67 | 67 | 67
Expected total cost | 565 | 565 | 565
Contract termination costs incurred | 1 | 3 | 91
Expected contract termination cost remaining | $ 95 | $ 95 | $ 95

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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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