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v3.20.4

Supplementary cash flow information (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Jul. 01, 2018 | Dec. 31, 2020 | Dec. 31, 2019
Non-cash investing activities |  |  |  |
Proceeds from sale of West Epsilon rig | $ 0 | $ 0 | $ 12 | $ 0
Non-cash financing activities |  |  |  |
Repayment of debt following sale of West Epsilon rig (1) | $ 0 | $ 0 | $ (12) | $ 0

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- Definition Noncash or Part Noncash Divestiture, Sale of Machinery and Equipment + References No definition available. + Details
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