Variable Interest Entities - Summary of Sale and Leaseback Arrangements (Details) $ in Millions	Dec. 31, 2019 USD ($) rig
Variable Interest Entity [Line Items]
Number of semi submersible rigs under sale leaseback arrangements \| rig	2
West Taurus
Variable Interest Entity [Line Items]
Sale value	$ 850
First repurchase option	418
Last repurchase option	154
West Hercules
Variable Interest Entity [Line Items]
Sale value	850
First repurchase option	580
Last repurchase option	138
West Linus
Variable Interest Entity [Line Items]
Sale value	600
First repurchase option	370
Last repurchase option	170
Repurchase obligation	$ 86

The repurchase amount under the first repurchase option pursuant to the sale and leaseback arrangement.

No definition available.

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Namespace Prefix:	sdrl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The repurchase amount under the last repurchase option pursuant to the sale and leaseback arrangement.

+ References

No definition available.

+ Details

Name:	sdrl_LastRepurchaseOption
Namespace Prefix:	sdrl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of semi-submersible rigs leased by the Company under sale and leaseback arrangements.

+ References

No definition available.

+ Details

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Namespace Prefix:	sdrl_
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- Definition

The agreed amount of the repurchase obligation at the end of the lease terms pursuant to the sale and leaseback arrangement.

+ References

No definition available.

+ Details

Name:	sdrl_RepurchaseObligation
Namespace Prefix:	sdrl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The net book value of the asset(s) sold in connection with the sale of the property to another party and lease back to the seller.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 51
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51840-112757

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 40
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77888430&loc=SL77919786-209982

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51843-112757

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51831-112757

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

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Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_SaleLeasebackTransactionDescriptionAxis=sdrl_WestHerculesMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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