Unconsolidated Affiliates (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Investments
Related party receivable	$ 26	$ 7
Related party payable	9
Transocean Norge
Investments
Equity method investment payment	$ 74	91
Ownership percentage	33.00%
Aggregate carrying amount of equity investment	$ 164	$ 91
Transocean Norge \| Reimbursements, Agent Fees and Other Receipts
Investments
Related party transaction	(96)
Transocean Norge \| Rent Expense
Investments
Affiliate costs	8
Transocean Norge \| Bareboat Charter Lease
Investments
Related party transaction	6
Other Investments \| Capital Expenditures
Investments
Related party transaction	7
Other Investments \| Research and Development
Investments
Related party transaction	$ 4

Costs associated with revenues arising from an entity that is an affiliate of the reporting entity by means of direct or indirect ownership.

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