Contracts with Customers - Contract Assets and Liabilities (Details) $ in Millions	Jun. 30, 2025 USD ($) customer	Dec. 31, 2024 USD ($)
Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract]
Accrued revenue	$ 137.6	$ 107.7
Current contract assets	137.6	107.7
Non-current contract assets	12.8	1.5
Total contract assets	150.4	109.2
Contract with Customer, Liability [Abstract]
Current deferred mobilization, demobilization and other revenue	(42.8)	(27.1)
Non-current deferred mobilization, demobilization and other revenue	(37.4)	(21.0)
Total contract liabilities	$ (80.2)	(48.1)
Customer with contract retention \| customer	1
Deferred variable rate revenue
Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract]
Accrued revenue	$ 16.0	20.4
Non-current contract assets	1.8	0.0
Deferred demobilization revenue
Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract]
Accrued revenue	9.0	1.0
Non-current contract assets	10.4	1.5
Customer retention
Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract]
Non-current contract assets	$ 0.6	$ 0.0

Number Of Customer with Contract Retention

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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