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Revenue from Contracts with Customers Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disaggregation of Revenue [Line Items] |  |  |
Capitalized Contract Cost, Net | $ 22.2 |  |
Minimum |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Drilling Contracts, Term | 1 month |  |
Maximum |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Drilling Contracts, Term | 2 years |  |
Upfront Rig Mobilizations And Certain Contract Preparation [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Capitalized Contract Cost, Net | $ 13.8 | $ 19.7 |
Capitalized Contract Cost, Amortization | 42.1 | 42.1 | $ 34.0
Deferred Certification Costs [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Capitalized Contract Cost, Net | 8.4 | 10.8 |
Capitalized Contract Cost, Amortization | $ 8.9 | $ 10.3 | $ 12.4

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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 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 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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- Details
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- Details
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