The number of individuals filing claims in a legal matter.

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- Definition

Number of crew deaths resulting from the dredge fire.

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No definition available.

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- Definition

The number of gallons of oil, diesel fuel, and contaminated water discharged during the fire.

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No definition available.

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- Definition

Number of lawsuits filed against the entity.

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No definition available.

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- Definition

Amount of increase in allowance for credit loss on accounts receivable, from recovery.

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- Definition

Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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- Definition

Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

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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.

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- Definition

Cash received for the settlement of litigation during the current period.

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- Definition

Disclosure of the unamortized amount of the discount on the note or receivable which is deducted from the face amount of the receivable or loan. The discount or premium is the difference between the present value and the face amount.

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Commitments and Contingencies - Narrative (Details) $ in Millions		3 Months Ended		12 Months Ended
	Aug. 21, 2018 gal item	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) claim lawsuit
Settled Litigation
Other Commitments [Line Items]
Legal settlement			$ 5.5
Notes receivable, current				$ 0.8
Notes receivables, noncurrent				1.8
Receivable, unamortized discount				$ 0.2
Recovery of reserved accounts receivable		$ 0.9
Waymon L Boyd Dredge Fire
Other Commitments [Line Items]
Number of crew deaths \| item	5
Number of gallons of oil, diesel fuel, and contaminated water discharged \| gal	18,000
Waymon L Boyd Dredge Fire \| Pending Litigation
Other Commitments [Line Items]
Number of lawsuits filed \| lawsuit				8
Number of claimants \| claim				13