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Revenue (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Revenue From Contract With Customer [Line Items] |  |  |
Revenue, remaining performance obligation | $ 327,147 |  |
Performance obligations exclude from dredging backlog | $ 50,000 |  |
Percentage of performance obligation to be recognized as revenue | 77.00% |  |
Performance obligation, expected to be recognized as revenue year | 2023 |  |
Remaining performance obligation, expected timing of satisfaction, year | 2024 |  |
Increased gross profit |  | $ 11,724 |
Amortization on pre-construction costs | $ 3,666 | $ 2,402 |
Other Current and Noncurrent Assets [Member] |  |  |
Revenue From Contract With Customer [Line Items] |  |  |
Costs to fulfill a contract with customer recognized as an asset | $ 3,971 |  | $ 4,472

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- Definition Amount of accumulated amortization of asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054 + Details
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