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v3.20.4

Leases - Narrative (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Jan. 01, 2019
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Leases [Abstract] |  |  |
Deferred rent and lease incentives | $ 20 | $ 22 | $ 24
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] | us-gaap:OtherLiabilities | us-gaap:OtherLiabilities | us-gaap:OtherLiabilities

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- Definition Deferred rent and Lease incentives + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Indicates line item in statement of financial position that includes current operating lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918631-209977 + Details
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Namespace Prefix: | us-gaap_
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