Commitments and Contingencies - (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) claim
SunGard
Loss Contingencies
Business combination, contingent liability	$ 77
Potential Tax Liability \| Pending Litigation \| Secretariat of the Federal Revenue Bureau of Brazil
Loss Contingencies
Loss contingency, number of claims pending \| claim	11
Loss contingency, value of damages sought	$ 15
Loss contingency, number of potential new claims filed \| claim	25
Loss contingency, potential additional claims amount ought	$ 56
Loss contingency, number of total pending and potential pending claims \| claim	36
Potential Tax Liability \| Pending Litigation \| Secretariat of the Federal Revenue Bureau of Brazil \| Maximum
Loss Contingencies
Loss contingency, estimate of possible loss	$ 71

Loss Contingency, Potential Additional Claims, Damages Sought

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- Definition

Loss Contingency, Potential New Claims Filed, Number

+ References

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- Definition

Loss Contingency, Total Pending and Potential Pending Claims, Number

+ References

No definition available.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
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-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

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