Business Combinations - Results of operations related to the rigs (Details) - Aquadrill LLC - USD ($) $ in Millions	3 Months Ended	4 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2022	Jun. 30, 2023
Business Combination Segment Allocation [Line Items]
Operating revenue	$ 414	$ 291	$ 402	$ 758
Profit/(loss) from continuing operations	82	(48)	(67)	121
Tender Rigs
Business Combination Segment Allocation [Line Items]
Operating revenue	6	0	0	12
Profit/(loss) from continuing operations	(2)	(2)	(3)	(3)
Gulfdrill rigs
Business Combination Segment Allocation [Line Items]
Operating revenue	7	7	10	14
Profit/(loss) from continuing operations	$ 6	$ 3	$ 4	$ 13

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Subparagraph (h)(2)
-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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