Commitments and Contingencies (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) claim
Secretariat of the Federal Revenue Bureau of Brazil [Member] \| Pending litigation [Member] \| Potential tax liability [Member]
Loss Contingencies [Line Items]
Loss contingency, number of claims pending \| claim	11
Loss contingency, value of damages sought	$ 15
Loss contingency, number of additional claims filed \| claim	24
Loss contingency, potential additional claims amount sought	$ 56
Number of total pending and potential pending claims \| claim	35
Secretariat of the Federal Revenue Bureau of Brazil [Member] \| Pending litigation [Member] \| Potential tax liability [Member] \| Maximum [Member]
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	$ 71
SunGard [Member]
Loss Contingencies [Line Items]
Liability for acquired contingencies	$ 75

Loss Contingency, Potential Additional Claims, Damages Sought

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- Definition

Loss Contingency, Potential New Claims Filed, Number

+ References

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Loss Contingency, Total Pending and Potential Pending Claims, Number

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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
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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.

+ References

No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Number of pending claims pertaining to a loss contingency.

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