Long Term Debt - Schedule of Long-term Debt Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 371,426	$ 400,955
Current portion due within one year	(57,567)	(31,602)
Unamortized debt discount	(28,154)	(33,398)
Deferred financing costs	(3,149)	(3,193)
Long-term debt, less current portion	282,556	332,762
Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	365,926	395,455
Non-Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	5,500	5,500
Old Convertible 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	71,313	86,470
Sea-Cat Crewzer III Term Loan Facility \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	16,703	19,178
SEACOR Offshore Delta (f/k/a SEACOSCO) Acquisition Debt \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	16,205	18,705
SEACOR Delta (f/k/a SEACOSCO) Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	79,759	86,316
SEACOR Alpine Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	28,484	29,734
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
SEACOR Offshore OSV \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	16,823	18,052
Tarahumara Shipyard Financing \| Recourse Long-Term Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 6,139	$ 6,500

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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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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