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Company Overview (Details) $ in Thousands | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 USD ($) item | Jun. 30, 2021 USD ($) segment item | Mar. 31, 2021
Segment Reporting Information [Line Items] |  |  |
Number of reportable segments | segment |  | 3 |
Acquisition of redeemable noncontrolling interests | $ |  | $ 2,268 |
Well Intervention |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of long-term chartered vessels | item | 2 | 2 |
Robotics |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of long-term chartered vessels | item | 2 | 2 |
STL |  |  |
Segment Reporting Information [Line Items] |  |  |
Percentage of ownership interest |  |  | 70.00%
Controlling interest acquired, ownership percentage | 30.00% |  |
Acquisition of redeemable noncontrolling interests | $ | $ 2,300 |  |

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