Long-Lived Assets (Impairments) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2025
Long-Lived Assets.
Aggregate loss on impairment of assets held for sale	$ 1,136	$ 1,136
Aggregate loss on impairment of assets held for sale, net of tax	$ 1,130	$ 1,130
Loss associated with impairment, net of tax (per share)	$ 1.27	$ 1.27

Represents the loss recognized for an asset classified as held for sale in continuing operations, net of tax.

No definition available.

Name:	rig_LongLivedAssetsHeldForSaleImpairmentChargeContinuingOperationsNetOfTax
Namespace Prefix:	rig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_AssetsNoncurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

After tax earnings per share or per unit impact arising from asset impairment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

+ Details

Name:	us-gaap_ImpairmentEffectOnEarningsPerShareAfterTax
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

+ Details

Name:	us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration