Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 22
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 40
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Drilling Contracts, Term

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Revenue from Contracts with Customers (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	$ 56.0		$ 56.0
Upfront Rig Mobilizations And Certain Contract Preparation [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	45.3		45.3		$ 47.4
Capitalized Contract Cost, Amortization	8.8	$ 25.7	21.6	$ 49.1
Deferred Certification Costs
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	10.7		10.7		$ 12.9
Capitalized Contract Cost, Amortization	$ 2.2	$ 2.5	$ 4.4	$ 5.6
Minimum
Capitalized Contract Cost [Line Items]
Remaining duration of drilling contracts	1 month		1 month
Maximum
Capitalized Contract Cost [Line Items]
Remaining duration of drilling contracts	5 years		5 years