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Rowan Transaction Assets Acquired Liabilities Assumed (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Apr. 11, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Business Acquisition [Line Items] |  |  |
Business Combination, Bargain Purchase, Adjustment (Gain) Loss | $ 712.8 | $ 6.3 | $ 75.8

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Business Combination, Bargain Purchase, Adjustment (Gain) Loss + References No definition available. + Details
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