Debt Instrument, Issued As A Percent Of Par

No definition available.

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Namespace Prefix:	sdrl_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	sdrl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Period Type:	duration

- Definition

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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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.

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+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

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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- Definition

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.

+ References

+ Details

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Details

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- Details

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Debt - Narrative (Details) kr in Millions, $ in Millions		9 Months Ended
Debt - Narrative (Details) kr in Millions, $ in Millions	Jul. 27, 2023 USD ($)	Sep. 30, 2025 USD ($)	Aug. 31, 2025 NOK (kr)	Dec. 31, 2024 USD ($)	Aug. 31, 2023 USD ($)	Jul. 31, 2023 USD ($)	Feb. 23, 2022 USD ($)
Debt Instrument [Line Items]
Long-term debt		$ 612		$ 610
SFL Hercules Ltd
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure, undiscounted		57	kr 574
Second Lien Facility \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount		575			$ 75	$ 500
Debt instrument, interest rate (as percent)					8.375%	8.375%
Debt issued as a percent of par (as a percent)					100.75%
Five Year First Lien Revolving Credit Facility \| SFL Hercules Ltd
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure, undiscounted		40	kr 403
Five Year First Lien Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term	5 years
Maximum borrowing capacity	$ 225
Line of credit facility, accordion feature, increase limit	100
Five Year First Lien Revolving Credit Facility \| Revolving Credit Facility \| SFL Hercules Ltd
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 185
Five Year First Lien Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Long-term debt	$ 50
Unsecured senior convertible bond \| Convertible debt
Debt Instrument [Line Items]
Debt instrument, face amount							$ 50
Debt instrument, interest rate (as percent)							6.00%
Debt conversion, converted instrument ratio		0.0526316