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Revenue from Contracts with Customers (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Capitalized Contract Cost [Line Items] |  |  |
Capitalized Contract Cost, Net | $ 18.9 |  |
Upfront Rig Mobilizations And Certain Contract Preparation [Member] |  |  |
Capitalized Contract Cost [Line Items] |  |  |
Capitalized Contract Cost, Net | 11.2 |  | $ 13.8
Capitalized Contract Cost, Amortization | 5.8 | $ 11.5 |
Deferred Certification Costs |  |  |
Capitalized Contract Cost [Line Items] |  |  |
Capitalized Contract Cost, Net | 7.7 |  | $ 8.4
Capitalized Contract Cost, Amortization | $ 2.6 | $ 3.1 |
Minimum [Member] |  |  |
Capitalized Contract Cost [Line Items] |  |  |
Remaining duration of drilling contracts | 1 month |  |
Maximum [Member] |  |  |
Capitalized Contract Cost [Line Items] |  |  |
Remaining duration of drilling contracts | 2 years |  |

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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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- Definition 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. + References No definition available. + Details
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- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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- Definition Drilling Contracts, Term + References No definition available. + Details
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