Contract revenue expense net.

No definition available.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

+ Details

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- Definition

Amount of interest income earned from interest-bearing assets owed to the entity by related party.

+ References

No definition available.

+ Details

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- Definition

Costs incurred to operate and maintain an entities' wells and related equipment and facilities, including depreciation and applicable operating costs of support equipment and facilities and other costs of operating and maintaining those wells and related equipment and facilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 23
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62136-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 25
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e65139-109465

+ Details

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Period Type:	duration

- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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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
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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Related Party Transactions - Schedule of Related Party Transactions (Parenthetical) (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Derivatives recharged to Seadrill Partners	$ (4,000,000)	$ 7,000,000
Seadrill Partners LLC [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Revenues related party	35,000,000	37,000,000
Rig operating costs charged by Seadrill Partners	1,000,000	2,000,000
Bareboat charter arrangements	0	3,000,000
Interest income, related party	0	5,000,000
Derivatives recharged to Seadrill Partners		(1,000,000)
Seadrill Partners LLC [Member] \| Subsidiaries [Member] \| Interest Rate Swap [Member]
Related Party Transaction [Line Items]
Derivatives recharged to Seadrill Partners	0	1,000,000
Seadrill Partners LLC [Member] \| Rig Operating Expenses Charged [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Other revenues	1,000,000	13,000,000
Seadrill Partners LLC [Member] \| Deferred Consideration Receivable [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Receivables (payables)	41,000,000		$ 52,000,000
Seadrill Partners LLC [Member] \| Insurance Premiums Charged [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Other revenues	$ 5,000,000	$ 5,000,000