Commitments and Contingencies (Narratives) (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) claim	Jan. 01, 2019 USD ($)
SunGard
Loss Contingencies
Liability for acquired contingencies	$ 64
Maximum \| Subsequent Event \| Scenario, Forecast
Loss Contingencies
Right of use asset		$ 500
Operating lease liability		500
Minimum \| Subsequent Event \| Scenario, Forecast
Loss Contingencies
Right of use asset		400
Operating lease liability		$ 400
Pending litigation \| Secretariat of the Federal Revenue Bureau of Brazil \| Potential tax liability
Loss Contingencies
Loss contingency, number of claims pending \| claim	12
Loss contingency, value of damages sought	$ 14
Loss contingency, number of additional claims filed \| claim	25
Loss contingency, potential additional claims amount sought	$ 50
Number of total pending and potential pending claims \| claim	37
Pending litigation \| Secretariat of the Federal Revenue Bureau of Brazil \| Potential tax liability \| Maximum
Loss Contingencies
Loss contingency, estimate of possible loss	$ 64
Reliance \| Pending litigation
Loss Contingencies
Loss contingency, value of damages sought	$ 125

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Loss Contingency, Potential New Claims Filed, Number

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

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

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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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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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