Commitments and Contingencies - (Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($) claim
Potential Tax Liability \| Pending Litigation \| Secretariat of the Federal Revenue Bureau of Brazil
Loss Contingencies [Line Items]
Loss contingency, number of claims pending \| claim	11
Loss contingency, value of damages sought	$ 15
Loss contingency, number of potential new claims filed \| claim	23
Loss contingency, potential additional claims amount ought	$ 56
Loss contingency, number of total pending and potential pending claims \| claim	34
Potential Tax Liability \| Pending Litigation \| Secretariat of the Federal Revenue Bureau of Brazil \| Maximum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	$ 71
SunGard
Loss Contingencies [Line Items]
Business combination, contingent liability	$ 89

Loss Contingency, Potential Additional Claims, Damages Sought

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Loss Contingency, Potential New Claims Filed, Number

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Loss Contingency, Total Pending and Potential Pending Claims, Number

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The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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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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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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