XML 187 R175.htm IDEA: XBRL DOCUMENT
v3.20.4

Related party transactions - Fair Value Gain/Loss on Convertible Bond (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Jul. 01, 2018 | Dec. 31, 2020 | Dec. 31, 2018
Related Party Transaction [Line Items] |  |  |  |
Fair value (loss) / gain | $ (11) | $ 0 | $ (29) | $ 0
Archer | Fair value gain/ (loss) of Archer debt component |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Fair value (loss) / gain | 3 | (3) | 4 | 2
Archer | Fair value gain/ (loss) of Archer embedded conversion option |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Fair value (loss) / gain | $ 0 | $ (9) | $ 3 | $ 2

X
- Definition Related Party Transaction, Fair Value Gain (Loss) On Convertible Bond Receivable + References No definition available. + Details
Name: | sdrl_RelatedPartyTransactionFairValueGainLossOnConvertibleBondReceivable
Namespace Prefix: | sdrl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sdrl_ArcherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionAxis=sdrl_FairValueLossGainOnDebtComponentOfConvertibleBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionAxis=sdrl_FairValueLossGainOnEmbeddedConversionOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |