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Backstop Parties, Equity Commitment Premium Percentage

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Percent Of Common Stock Received Less The Rights Offering Percentage, Back Stop Parties

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Rights Offering Percentage

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Contractual interest rate for funds borrowed, under the debt agreement.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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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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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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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Chapter 11 - Seadrill Proceedings (Details) - USD ($) $ in Millions	Feb. 10, 2021	Dec. 31, 2021	Dec. 31, 2020	Jul. 02, 2018
Reorganization, Chapter 11 [Line Items]
Long-term debt	$ 6,200	$ 5,662	$ 5,662
Rights Offering Percentage	12.50%
Backstop Parties, percentage of new shares issued minus the Rights Offering Percentage (if under-subscribed)	12.50%
Equity commitment premium percentage	4.25%
Commitment premium	7.50%
Reorganized Seadrill \| Maximum
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by parent	83.00%
Reorganized Seadrill \| Minimum
Reorganization, Chapter 11 [Line Items]
Noncontrolling interest, ownership percentage by parent	16.75%
Credit Facility Maturing 2027
Reorganization, Chapter 11 [Line Items]
Long-term debt			$ 5,662
Senior Secured Notes Member \| Secured Debt
Reorganization, Chapter 11 [Line Items]
Long-term debt	$ 500
Debt instrument, interest rate (as percent)				12.00%
Allowed Credit Agreement Claim
Reorganization, Chapter 11 [Line Items]
Long-term debt	$ 683
Stated interest rate, paid-in-kind portion (as a percent)	7.50%
Allowed Credit Agreement Claim \| LIBOR
Reorganization, Chapter 11 [Line Items]
Basis spread on variable rate (as a percent)	5.00%
New First Lien Facility
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity	$ 300
New First Lien Term Loan
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity	$ 175
Debt instrument, interest rate (as percent)	7.00%
New First Lien Revolving Credit Facility
Reorganization, Chapter 11 [Line Items]
Maximum borrowing capacity	$ 125
Debt instrument, interest rate (as percent)	7.00%
Commitment fee percentage	2.80%