General information (Details)	Jun. 30, 2019 drilling_unit
Property, Plant and Equipment [Line Items]
Number of offshore drilling units owned by the Company	35
Seadrill Partners, SeaMex, Sonangol and Northern Drilling
Property, Plant and Equipment [Line Items]
Number of offshore drilling units owned by the Company	20

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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