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Nominal or face amount used to calculate payment on derivative.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Chapter 11 - Narrative (Details) - USD ($)			2 Months Ended
Chapter 11 - Narrative (Details) - USD ($)	Feb. 28, 2022	Feb. 10, 2021	Feb. 22, 2022	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Feb. 23, 2022	Jan. 20, 2022	Nov. 02, 2021
Reorganization, Chapter 11 [Line Items]
Total debt				$ 355,000,000	$ 518,000,000		$ 951,000,000
Rights offering percentage		12.50%
Backstop parties, equity commitment premium percentage		4.25%
Backstop parties, commitment premium		7.50%
Backstop parties, commitment premium		$ 20,000,000
% allocation			100.00%
Reorganization value, rig asset derecognized			$ 175,000,000
Reorganization value, financial liability rig asset derecognized			161,000,000
Reorganization value, cash held as collateral			7,000,000
Interest expense, not recorded due to reorganization			$ 48,000,000
Paratus Energy Services
Reorganization, Chapter 11 [Line Items]
Ownership interest (as percent)				35.00%		35.00%		35.00%
Class 4 credit agreement claimants
Reorganization, Chapter 11 [Line Items]
% allocation			83.00%
Rights offering participants
Reorganization, Chapter 11 [Line Items]
% allocation			12.50%
Backstop parties
Reorganization, Chapter 11 [Line Items]
% allocation			4.25%
Class 9 predecessor shareholders
Reorganization, Chapter 11 [Line Items]
% allocation			0.25%
NSNCo \| SeaMex Limited
Reorganization, Chapter 11 [Line Items]
Business acquisition, percentage of voting interests acquired									100.00%
NSNCo
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners						35.00%		35.00%
NSNCo \| NSNCo Noteholders
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by parent								65.00%
Maximum \| Reorganized Seadrill
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by parent		83.00%
Minimum \| Reorganized Seadrill
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by parent		16.75%
Allowed credit agreement claim
Reorganization, Chapter 11 [Line Items]
Total debt		$ 683,000,000
First Lien Senior Secured (Level 3)
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity		300,000,000
New first lien term loan
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity		175,000,000
New first lien revolving credit facility
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity		$ 125,000,000
Hermen convertible bond \| Convertible debt
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	$ 50,000,000
Debt conversion, converted instrument, shares issued	52.6316
Derivative notional amount	$ 1,000