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Basis of Presentation and Accounting Policies - Additional Information (Details) - USD ($) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025 | Dec. 31, 2024
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Unearned revenue | $ 922,000 |  | $ 1,096,000 | $ 2,534,000
Capitalized interest costs, including allowance for funds used during construction, total | 1,000,000 | $ 0 |  |
Impairment of long-lived assets owned or leased in vessels | $ 0 | $ 0 |  |
Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration] | Gains on Asset Dispositions and Impairments, Net | Gains on Asset Dispositions and Impairments, Net |  |
Assets held for sale | $ 13,376,000 |  | $ 10,812,000 |
Equity method investment, other than temporary impairment | $ 0 | $ 0 |  |
Effective income tax rate reconciliation, percent | 16.20% |  |  |
Class of warrant or right, exercise price of warrants or rights | $ 0.01 |  |  |
Restricted Stock |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Antidilutive securities excluded from computation of loss per share, amount | 1,027,186 | 1,266,954 |  |
Employee Stock Option |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Antidilutive securities excluded from computation of loss per share, amount | 1,006,365 | 1,008,865 |  |
Offshore Support Vessels |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Estimated useful life (Year) | 20 years |  |  |
Platform Supply Vessel One [Member] | UNITED STATES |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Assets held for sale | $ 5,500,000 |  |  |
Platform Supply Vessel | Middle East and Asia |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Assets held for sale | 500,000 |  |  |
Liftboats 1 | UNITED STATES |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Assets held for sale | 3,200,000 |  |  |
Liftboats 2 | UNITED STATES |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Assets held for sale | 3,200,000 |  |  |
Fast Support Vessel | Africa and Europe |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Assets held for sale | $ 900,000 |  |  |
Equity Investments in 50% or Less Owned Companies | Minimum |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Equity method investment, ownership percentage | 20.00% |  |  |
Equity Investments in 50% or Less Owned Companies | Maximum |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Equity method investment, ownership percentage | 50.00% |  |  |
Equity Investments in 50% or Less Owned Companies | SEACOR Marine Foreign Holdings | Minimum |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Equity method investment, ownership percentage | 50.00% |  |  |
Accounting Standards Update 2023-09 |  |  |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |  |  |
Change in accounting principle, accounting standards update, adopted [true false] | true |  |  |
Change in accounting principle, accounting standards update, immaterial effect [true false] | true |  |  |

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