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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The 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 within one year (or one business cycle).

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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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The increase (decrease) during the reporting period in receivables to be collected from other entities that could exert significant influence over the reporting entity.

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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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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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Related party transactions - Analysis of Related Party Receivable Balances (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2018	Jul. 01, 2018	Dec. 31, 2019	Dec. 31, 2017	Nov. 30, 2016	Mar. 31, 2015
Related Party Transaction [Line Items]
Total related party receivables	$ 716		$ 704
Repayments received against related party loans	(7)	$ 13	43	$ 42
Amount due from related parties - current	177		181
Amount due from related parties - non-current	539		523
Related party loans and interest
Related Party Transaction [Line Items]
Total related party receivables	476		488
Deferred consideration arrangements
Related Party Transaction [Line Items]
Total related party receivables	59		31
Convertible bond
Related Party Transaction [Line Items]
Total related party receivables	43		35
Trading balances
Related Party Transaction [Line Items]
Total related party receivables	138		150
SeaMex seller's credit and loans receivable \| Related party loans and interest
Related Party Transaction [Line Items]
Total related party receivables	398		$ 422
Interest rate on related party receivable			6.50%
SeaMex seller's credit and loans receivable \| Sellers credit
Related Party Transaction [Line Items]
Total related party receivables						$ 250
SeaMex seller's credit and loans receivable \| Working capital loan
Related Party Transaction [Line Items]
Total related party receivables					$ 45
SeaMex seller's credit and loans receivable \| Accrued interest
Related Party Transaction [Line Items]
Total related party receivables			$ 127
Seabras loans receivable \| Related party loans and interest
Related Party Transaction [Line Items]
Total related party receivables	78		66
Repayments received against related party loans			15
Seabras loans receivable \| Accrued interest
Related Party Transaction [Line Items]
Total related party receivables			12
Seabras loans receivable \| Loan principal
Related Party Transaction [Line Items]
Total related party receivables			54
Seabras loans receivable \| Shareholder loans
Related Party Transaction [Line Items]
Repayments received against related party loans			9
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners
Related Party Transaction [Line Items]
Total related party receivables	59		31
West Vela \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners \| Mobilization receivable
Related Party Transaction [Line Items]
Total related party receivables	31		17
West Vela \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners \| Share of dayrate
Related Party Transaction [Line Items]
Total related party receivables	27		14
West Vela \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners \| Share of dayrate \| Fair value
Related Party Transaction [Line Items]
Total related party receivables	29
West Polaris \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners
Related Party Transaction [Line Items]
Total related party receivables	1		$ 0
West Polaris \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Seadrill Partners \| Fair value
Related Party Transaction [Line Items]
Total related party receivables	$ 1
Minimum \| LIBOR \| Seabras loans receivable \| Related party loans and interest
Related Party Transaction [Line Items]
Interest rate on related party receivable			3.40%
Maximum \| LIBOR \| Seabras loans receivable \| Related party loans and interest
Related Party Transaction [Line Items]
Interest rate on related party receivable			3.99%