Number of shares of equity interests issued or issuable to acquire entity.

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Exercise price per share or per unit of warrants or rights outstanding.

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Face amount per share of no-par value common stock.

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Shareholders' Equity (Share Issuance Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			4 Months Ended	12 Months Ended
	Apr. 30, 2021	Apr. 11, 2019	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2020
Shares Issuance [Line Items]
Stock Issued During Period, Shares, New Issues	75,000,000.0
Common Stock, Value, Outstanding	$ 8.5		$ 8.5
Common shares, shares issued				75,000,000
Class of Warrant or Right, Outstanding				5,645,161
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 131.88
Warranted, Period Exercisable				7 years
Management Incentive Plan
Shares Issuance [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	8,960,573		8,960,573
Rowan Companies [Member]
Shares Issuance [Line Items]
Business Combination, Consideration Transferred		$ 1,400.0
Class A Ordinary Shares, U.S. [Member]
Shares Issuance [Line Items]
Common shares, shares issued						206,100,000
Class A Ordinary Shares, U.S. [Member] \| Rowan Companies [Member]
Shares Issuance [Line Items]
Number of ordinary shares		88,300,000
Shares Issued, Price Per Share		$ 15.88
Common Stock [Member]
Shares Issuance [Line Items]
Stock Issued During Period, Shares, New Issues	75,000,000
Common shares, shares issued	700,000,000		700,000,000
Common Stock, No Par Value	$ 0.01		$ 0.01
Preferred Stock
Shares Issuance [Line Items]
Common shares, shares issued	150,000,000		150,000,000	0
Common Stock, No Par Value	$ 0.01		$ 0.01
Common Stock [Member]
Shares Issuance [Line Items]
Stock Issued During Period, Shares, New Issues			75,000,000.0		88,000,000.0