Long Term Debt - Schedule of Long-term Debt Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 400,955	$ 521,877
Current portion due within one year	(31,602)	(32,377)
Unamortized debt discount	(33,398)	(44,864)
Deferred financing costs	(3,193)	(4,126)
Long-term debt, less current portion	332,762	440,510
Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	395,455	399,028
Non-Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	5,500	122,849
Convertible Senior Notes \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	125,000	125,000
SEACOR Marine Foreign Holdings Credit Facility \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	86,470	100,750
Sea-Cat Crewzer III Term Loan Facility \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	19,178	21,653
SEACOR Offshore Delta (f/k/a SEACOSCO) Acquisition Debt \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	18,705	19,705
SEACOR Delta (f/k/a SEACOSCO) Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	86,316	95,317
SEACOR Alpine Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	29,734	31,103
SEACOR 88/888 Term Loan \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	5,500	5,500
SEACOR 88/888 Term Loan \| Non-Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	5,500	5,500
Tarahumara Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	6,500
SEACOR Offshore OSV \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 18,052
Falcon Global U S A Term Loan Facility \| Non-Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross		102,349
Falcon Global USA Revolver \| Non-Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross		15,000
Windcat Workboats Facilities
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 27,626

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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