Risk Exposure Associated With Instruments

No definition available.

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- Definition

Sensitivity Analysis For Interest Rate Risk, Reasonably Possible Change In Risk Variable, Debt

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- 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_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeAmountOfHedgedItem
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value of all derivatives designated as interest rate fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=sdrl_SecuredCreditFacilityMember
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- Details

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- Details

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- Details

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- Details

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Risk management and financial instruments - Interest Rate Risk (Details) - USD ($) $ in Millions	Jun. 30, 2019	Apr. 10, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Principal outstanding	$ 6,765		$ 7,086
Principal outstanding	5,296
Hedging instruments	4,500
Net exposure	338
Impact of 1% increase in rates	27
Secured debt \| Secured credit facilities
Debt Instrument [Line Items]
Principal outstanding	5,662		5,662
Hedging instruments	4,500
Net exposure	1,162
Impact of 1% increase in rates	36
Secured debt \| Credit facilities contained within variable interest entities
Debt Instrument [Line Items]
Principal outstanding	645		655
Net exposure	645
Impact of 1% increase in rates	6
Secured debt \| New Secured Notes
Debt Instrument [Line Items]
Principal outstanding	458	$ 311	$ 769
Impact of 1% increase in rates	0
Total floating rate debt obligations
Debt Instrument [Line Items]
Principal outstanding	6,307
Hedging instruments	4,500
Net exposure	1,807
Impact of 1% increase in rates	42
Less: Cash and Restricted Cash
Debt Instrument [Line Items]
Principal outstanding	1,469
Net exposure	1,469
Impact of 1% increase in rates	$ 15