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Marketable securities - Marketable Securities Held (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Gain (Loss) on Securities [Line Items] |  |
Total marketable securities | $ 8 | $ 11
Seadrill Partners- Common units |  |
Gain (Loss) on Securities [Line Items] |  |
Total marketable securities | 0 | 2
Archer |  |
Gain (Loss) on Securities [Line Items] |  |
Total marketable securities | $ 8 | $ 9

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- Definition Amount of investment in marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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