Long-Term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. This does not include advances to clients.

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Percentage added to reference rate used to compute variable rate on loan receivable.

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The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

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Amount of transactions with related party during the financial reporting period.

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Unconsolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Unconsolidated Affiliates (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020
Investments
Loss on impairment of investment in unconsolidated affiliates			$ 59
Aggregate carrying amount of equity investment		$ 135			$ 138
Investments in loans to unconsolidated affiliates		$ 33
Orion/Transocean Norge
Investments
Ownership percentage		33.00%
Loss on impairment of investment in unconsolidated affiliates			59
Aggregate carrying amount of equity investment		$ 100			$ 104
Related party transaction	$ 3		$ 35
Investments in loans to unconsolidated affiliates		33
Affiliate loan receivable		$ 33
Orion/Transocean Norge \| LIBOR
Investments
Loan receivable interest rate (as a percent)				6.50%
Orion/Transocean Norge \| Orion/Transocean Norge
Investments
Loan payable				$ 100
Orion/Transocean Norge \| Discount rate
Investments
Investment fair value measurement		12