- Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2017	Sep. 30, 2018	Dec. 31, 2017
Intangible assets with finite lives
Gross Carrying Amount		$ 3,731	$ 4,013
Accumulated Amortization and Impairment		2,471	2,280
Net Carrying Amount		1,260	1,733
Estimated amortization for intangible assets
Remainder of 2018		100
2019		386
2020		222
2021		128
2022		85
Thereafter		339
Total		1,260
Customer related and contract based
Intangible assets with finite lives
Gross Carrying Amount		2,305	2,550
Accumulated Amortization and Impairment		1,457	1,415
Net Carrying Amount		848	1,135
Tradenames
Intangible assets with finite lives
Gross Carrying Amount		1,030	1,047
Accumulated Amortization and Impairment		687	533
Net Carrying Amount		343	514
Technology and other
Intangible assets with finite lives
Gross Carrying Amount		396	416
Accumulated Amortization and Impairment		327	332
Net Carrying Amount		$ 69	$ 84
Discontinued Operations, Disposed of by Sale \| Tempo Business \| Tradenames
Intangible assets with finite lives
Impairment of tradename	$ 380

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Subparagraph (b)
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-Publisher FASB
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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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