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v3.20.4

Fresh Start Accounting - Schedule of Weighted Average Cost of Capital (Details) |  | 12 Months Ended
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Jul. 02, 2018 | Dec. 31, 2020
Restructuring Cost and Reserve [Line Items] |  |
WACC |  | 11.40%
Seadrill Capricorn Holdings LLC |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 11.40% |
Seadrill Operating LP |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 12.00% |
Seadrill Deepwater Drillship Ltd |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 12.00% |
Seabras Sapura Holding |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 14.30% |
Seabras Sapura Participacoes |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 13.70% |
SeaMex |  |
Restructuring Cost and Reserve [Line Items] |  |
WACC | 12.70% |

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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. + References No definition available. + Details
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