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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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- Definition The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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- Definition The total number of new claims filed pertaining to a loss contingency during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349 + Details
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