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

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.

No definition available.

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