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Revenue, Contract Assets and Liabilities and Other Contract Matters -Summary of Remaining Performance Obligation by Operating Segment (Parenthetical) (Details) $ in Millions | Sep. 30, 2020 USD ($) vessel | Mar. 31, 2018 vessel
--- | --- | ---
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |
Number of multi-purpose service vessels | vessel | 2 | 2
Shipyard | Disputes |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |
Remaining performance obligation | $ | $ 21.9 |

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- Details
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