Commitments and Contingencies - Data Security Incident (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) lawsuit
Data Security Incident
Loss Contingencies [Line Items]
Expense related to data security incident	$ 44
Insurance recoveries related to data security incident	$ 46
Putative Class Action Lawsuits Related to Data Security Incident
Loss Contingencies [Line Items]
Number of lawsuits filed \| lawsuit	100

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Number of pending claims pertaining to a loss contingency.

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