Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Components of deferred tax assets and liabilities. [Line Items]
Deferred tax assets, net of valuation allowance	$ 151.3
Deferred tax liabilities	9.4
Valuation allowance	19.2
Reserves for uncertain tax positions	188.6		$ 175.9
Unrecognized tax benefits	0.1		$ 0.3
Deferred tax expenses related to contract fair value amortization	4.2
Tax expenses (benefits) related to various recurring items		$ 0.8
Tax benefit related to deferred tax adjustments		1.3
Maersk Drilling Merger
Components of deferred tax assets and liabilities. [Line Items]
Net increase to reserves for uncertain tax positions	14.2
Foreign Tax Authority | GUYANA
Components of deferred tax assets and liabilities. [Line Items]
Deferred foreign tax expense (benefits)	(44.0)
Increase (decrease) of deferred tax assets valuation allowance		(3.8)
Foreign Tax Authority | SWITZERLAND
Components of deferred tax assets and liabilities. [Line Items]
Deferred foreign tax expense (benefits)	(6.1)
Foreign Tax Authority | LUXEMBOURG
Components of deferred tax assets and liabilities. [Line Items]
Deferred foreign tax expense (benefits)	4.5
Increase (decrease) of deferred tax assets valuation allowance	4.5
Foreign Tax Authority | Guyana, Luxembourg, And Switzerland
Components of deferred tax assets and liabilities. [Line Items]
Tax expenses (benefits) related to various recurring items	25.6
Foreign Tax Authority | Guyana And Switzerland
Components of deferred tax assets and liabilities. [Line Items]
Increase (decrease) of deferred tax assets valuation allowance	$ (50.1)
Foreign Tax Authority | Swiss Federal Tax Administration (FTA)
Components of deferred tax assets and liabilities. [Line Items]
Tax benefit related to deferred tax adjustments		$ 0.9