Average age of vessels.

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Business acquisition percentage of purchase price fixed accrued interest rate for membership interest in year four.

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Business acquisition percentage of purchase price fixed accrued interest rate for membership interest in year one.

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Business acquisition percentage of purchase price fixed accrued interest rate for membership interest in year three.

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Business acquisition percentage of purchase price fixed accrued interest rate for membership interest in two.

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Business acquisition purchase price amortization period.

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Business Acquisition Purchase price for membership interests annual installment payment in year four.

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Business acquisition purchase price for membership interests annual installment payment in year one.

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Business acquisition purchase price for membership interests annual installment payment in year three.

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Business acquisition purchase price for membership interests annual installment payment in year two.

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Business combination, assumed and guarantee amount.

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Business combination, purchase price payable to sellers at closing of transaction.

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Debt instrument quarterly principal payments.

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The number of vessels deliverd to the company.

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Number of vessels owned.

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Number of vessels owned with high specification

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Number of vessels owned with identical specification.

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Percentage of interest accrues under credit facility plus mandatory cost.

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Purchase price payable for equity method investment.

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Number of shares of equity interests issued or issuable to acquire entity.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of liabilities assumed at the acquisition date.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Description of reference rate used for variable rate of debt instrument.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Business Acquisitions - Additional Information (Details) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2021 USD ($) Vessel shares	Dec. 31, 2021 USD ($) Vessel shares	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($) Vessel	May 31, 2020
Merger Agreement \| Common Stock [Member] \| Merger Consideration
Common stock issued \| shares	1,567,935
OSV Partners \| Merger Agreement \| Limited Partner
Business combination, assumed and guarantee amount	$ 18.1
Quarterly principal payments	$ 0.5
Percentage of interest accrues under credit facility plus mandatory cost	4.68%
Debt instrument, maturity date	Dec. 31, 2023
OSV Partners \| Merger Agreement \| Limited Partner \| Platform Supply Vessels
Number of vessels owned \| Vessel	5	5
Percentage of voting interests acquired	100.00%	100.00%
Average age of vessels	7 years
OSV Partners \| Merger Agreement \| Common Stock [Member] \| Limited Partner
Common stock issued \| shares		1,567,935
OSV Partners \| Merger Agreement \| Common Stock [Member] \| Merger Consideration
Common stock issued \| shares	531,872	1,567,935
OSV Partners \| Merger Agreement \| Common Stock [Member] \| PIK Loan Consideration \| Limited Partner
Common stock issued \| shares	1,036,063
SEACOR Offshore Delta LLC \| Sale And Purchase Agreement
Purchase price payable for membership interest				$ 28.2
Purchase price payable to sellers at closing of transaction				8.4
Purchase price for membership interests annual installment payment in first year				1.0
Purchase price for membership interests annual installment payment in second year				2.5
Purchase price for membership interests annual installment payment in third year				2.5
Purchase price for membership interests annual installment payment in fourth year				$ 13.7
Purchase price fixed accrued interest rate in first year				1.50%
Purchase price fixed accrued interest rate in second year				7.00%
Purchase price fixed accrued interest rate in third year				7.50%
Purchase price fixed accrued interest rate in fourth year				8.00%
SEACOR Offshore Delta LLC \| Sale And Purchase Agreement \| Platform Supply Vessels
Number of vessels owned \| Vessel	8	8		8
Number of vessels owned with high specification \| Vessel	2	2
Number of vessels owned with identical specification \| Vessel	6	6
SEACOR Offshore Delta LLC \| Deferred Purchase Agreements \| Platform Supply Vessels
Business acquisition, aggregate amount outstanding	$ 86.3	$ 86.3	$ 95.3	$ 100.8
Business acquisition, amortization period of purchase price		10 years
Debt instrument, description of floating interest rate basis		three-month LIBOR plus 4.0
Debt instrument, basis spread on floating interest rate		4.00%
Number of vessels delivered to the company \| Vessel	7	7
SEACOR Offshore Delta LLC \| Merger Agreement \| Sale And Purchase Agreement
Percentage of voting interests acquired				100.00%
SEACOR Offshore Delta LLC \| Merger Agreement \| Sale And Purchase Agreement \| SEACOR Offshore Asia
Percentage of voting interests acquired					50.00%