Related party transaction management fee percentage.

No definition available.

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- Definition

Related party transaction management service agreement termination notice period.

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No definition available.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

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Face (par) amount of debt instrument at time of issuance.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Aggregate amount of receivables to be collected from related parties 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, at the financial statement date. which are usually due after one year (or one business cycle).

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Increase in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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

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No definition available.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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No definition available.

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The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

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- Definition

The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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- 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.

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No definition available.

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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.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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No definition available.

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Related Party Transactions - Additional Information (Detail) - USD ($)				6 Months Ended
	Jun. 30, 2018	Apr. 26, 2017	Feb. 28, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Nov. 30, 2016	Mar. 31, 2015
Related Party Transaction [Line Items]
Investment income, net				$ 19,000,000	$ 36,000,000
Seller's credit	$ 565,000,000			565,000,000		$ 547,000,000
Debt outstanding	8,547,000,000			8,547,000,000		8,701,000,000
Secured Debt [Member]
Related Party Transaction [Line Items]
Debt outstanding	5,476,000,000			5,476,000,000		5,581,000,000
Equity Method Investee [Member] \| Medium-term Notes [Member]
Related Party Transaction [Line Items]
Debt, face amount										$ 230,000,000
Archer [Member]
Related Party Transaction [Line Items]
Subordinated loan		$ 37,000,000
Loans payable fair value		56,000,000
Net gain on debt extinguishment		$ 19,000,000
Fair value of the convertible debt instrument	58,000,000			58,000,000
Gain on debt component	2,000,000
Gain on the embedded conversion option	4,000,000
Private placement			$ 100,000,000
Ownership interest		15.69%
Archer [Member] \| Embedded Derivative Option [Member]
Related Party Transaction [Line Items]
Fair value of the convertible debt instrument	12,000,000			12,000,000
Archer [Member] \| Debt [Member]
Related Party Transaction [Line Items]
Fair value of the convertible debt instrument	46,000,000			46,000,000
Archer [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Notes receivable							$ 37,000,000
Investment income, net				$ 0	3,000,000
Archer [Member] \| Equity Method Investee [Member] \| Convertible Subordinated Debt [Member]
Related Party Transaction [Line Items]
Due from related parties		$ 45,000,000
Seadrill Jack Up Operations DeMexico [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Ownership				100.00%
Related party expense				$ 1,000,000	3,000,000
SeaMex Limited [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Debt, face amount										250,000,000
Seller's credit	250,000,000			250,000,000		250,000,000				250,000,000
Debt outstanding	250,000,000			250,000,000		250,000,000
Loan to related party	45,000,000			45,000,000		45,000,000			$ 45,000,000
Interest income, related party				$ 12,000,000	17,000,000
Minimum [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Management fee				4.50%
Minimum [Member] \| Archer [Member]
Related Party Transaction [Line Items]
Ownership interest			16.23%
Minimum [Member] \| Seadrill Jack Up Operations DeMexico [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Management fee				5.00%
Maximum [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Management fee				8.00%
Maximum [Member] \| Archer [Member]
Related Party Transaction [Line Items]
Ownership interest			39.89%
Maximum [Member] \| Seadrill Jack Up Operations DeMexico [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Management fee				8.00%
LIBOR [Member] \| SeaMex Limited [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Loan receivable basis spread on variable rate									6.50%
Revolving Credit Facility [Member] \| SeaMex Limited [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Debt, face amount										$ 20,000,000
SeaMex Limited [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Management service agreement termination notice period				60 days
Other revenues				$ 5,000,000	5,000,000
SeaMex Limited [Member] \| Drilling Unit [Member] \| Equity Method Investee [Member]
Related Party Transaction [Line Items]
Maximum guarantee	30,000,000			30,000,000		30,000,000
SFL West Vela Limited [Member] \| 1.5 Billion Facility [Member] \| Secured Debt [Member]
Related Party Transaction [Line Items]
Debt, face amount	1,500,000,000			1,500,000,000
Sfl West Polaris Limited [Member] \| 420 Million Facility [Member] \| Secured Debt [Member]
Related Party Transaction [Line Items]
Debt, face amount	420,000,000			420,000,000
Performance Guarantee [Member] \| Seadrill Partners LLC [Member]
Related Party Transaction [Line Items]
Guarantees	57,000,000			57,000,000		165,000,000
Financial Guarantee [Member] \| Seadrill Partners LLC [Member]
Related Party Transaction [Line Items]
Guarantees						0
Financial Guarantee [Member] \| Archer [Member]
Related Party Transaction [Line Items]
Guarantees					$ 278,000,000		278,000,000
Subordinated loan							$ 149,000,000
Contingent liability recognized								$ 28,000,000
Custom Guarantee [Member] \| Seadrill Partners LLC [Member]
Related Party Transaction [Line Items]
Guarantees	$ 0			$ 0		$ 600,000