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Commitments and Contingencies - Expenses and Insurance Recoveries (Details) $ in Millions		1 Months Ended	3 Months Ended
	Nov. 30, 2018 lawsuit	Mar. 15, 2019 lawsuit	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Data Security Incident
Loss Contingencies [Line Items]
Expense related to data security incident			$ 5	$ 15
Insurance recoveries related to data security incident			5	17
Insurance recoveries received			$ 10	$ 24
Class Action Lawsuits Related to Data Security Incident
Loss Contingencies [Line Items]
Number of new lawsuits filed | lawsuit	100
Shareholder Derivative Complaints Related to Data Security Incident
Loss Contingencies [Line Items]
Number of new lawsuits filed | lawsuit		2

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Proceeds from Insurance Recoveries

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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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The total number of new claims filed pertaining to a loss contingency during the period.

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