XML 146 R134.htm IDEA: XBRL DOCUMENT v3.20.4

Investment in associated companies - Share in Results from Associated Companies (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2018	Jul. 01, 2018	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	$ (90)	$ 149	$ (77)	$ (115)
Seadrill Partners
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)			(75)
Seadrill Partners | Seadrill Partners - Direct ownership investments
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	(82)	77	(75)	(107)
Seadrill Partners | Seadrill Partners - Subordinated Units
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	(20)	22	0	(17)
Seabras Sapura
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	24	46	20	29
SeaMex
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	(12)	4	(22)	(19)
Sonadrill
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	0	0	(2)	(1)
Gulfdrill
Schedule of Equity Method Investments [Line Items]
Share in results from associated companies (net of tax)	$ 0	$ 0	$ 2	$ 0

X

- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

+ 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(12))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

+ Details

Name:	us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sdrl_SeadrillPartnersLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=sdrl_SeadrillPartnersDirectOwnershipInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=sdrl_SeadrillPartnersSubordinatedUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sdrl_SeabrasSapuraCompaniesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sdrl_SeaMexLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sdrl_SonadrillMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sdrl_GulfdrillMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: