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Long Term Debt - Additional Information (Details) - USD ($)				3 Months Ended			9 Months Ended
	Oct. 05, 2022	Sep. 29, 2022	Aug. 02, 2022	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Class of warrant or right, exercise price of warrants or rights					$ 0.01		$ 0.01
Cash and Cash Equivalents, Percentage							24.60%
Cash and Cash Equivalents					$ 71,300,000		$ 71,300,000
Long-term Debt Obligation
Debt Instrument [Line Items]
Letters of credit outstanding, amount					1,100,000		1,100,000
Subsequent Event \| Carlyle Warrants
Debt Instrument [Line Items]
Class of warrant or right, exercise price of warrants or rights	$ 0.01
Convertible Senior Notes due 2023 (Old Convertible Notes)
Debt Instrument [Line Items]
Convertible debt, total					$ 125,000,000.0		$ 125,000,000.0
Senior PIK Toggle Notes due 2026 \| Subsequent Event
Debt Instrument [Line Items]
Convertible debt, total	$ 90,000,000.0
Convertible Senior Notes due 2026 \| Subsequent Event
Debt Instrument [Line Items]
Convertible debt, total	$ 35,000,000.0
Debt instrument percentage	4.25%
Guaranteed Notes \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, redemption, description	SEACOR Marine may redeem some or all of the Guaranteed Notes at any time in minimum denominations of $10.0 million, upon not less than 30 nor more than 60 calendar days’ notice, at a price equal to (a) 102% of the principal amount of the Guaranteed Notes redeemed, if redeemed prior to October 1, 2023, (b) 101% of the principal amount of the Guaranteed Notes redeemed, if redeemed on or after October 1, 2023, but prior to October 1, 2024 and (c) 100% of the principal amount of the Guaranteed Notes redeemed, if redeemed on or after October 1, 2024, in each case plus accrued and unpaid interest, if any, to, but not including, the redemption date, provided, SEACOR Marine may not redeem the Guaranteed Notes if the principal amount of Guaranteed Notes and New Convertible Notes outstanding will be equal to or less than $50.0 million in the aggregate, unless SEACOR Marine redeems all of the Guaranteed Notes in whole.
Convertible notes outstanding	$ 50,000,000.0
Guaranteed Notes \| Subsequent Event \| Redeemed Prior to October 1, 2023
Debt Instrument [Line Items]
Redemption, percentage of principal amount	102.00%
Guaranteed Notes \| Subsequent Event \| Redeemed On or After October 1, 2024
Debt Instrument [Line Items]
Redemption, percentage of principal amount	100.00%
Guaranteed Notes \| Subsequent Event \| Redeemed On or After October 1, 2023 but Prior to October 1, 2024
Debt Instrument [Line Items]
Redemption, percentage of principal amount	101.00%
Guaranteed Notes \| Subsequent Event \| Cash Interest
Debt Instrument [Line Items]
Debt instrument percentage	8.00%
Guaranteed Notes \| Subsequent Event \| Hybrid Interest
Debt Instrument [Line Items]
Debt instrument percentage	9.50%
Guaranteed Notes \| Subsequent Event \| Hybrid Interest Payment in Kind
Debt Instrument [Line Items]
Debt instrument percentage	5.25%
Guaranteed Notes \| Subsequent Event \| Hybrid Interest Payment in Cash
Debt Instrument [Line Items]
Debt instrument percentage	4.25%
Old Convertible Notes \| Subsequent Event
Debt Instrument [Line Items]
Redemption, percentage of principal amount	4.25%
Maturity date	Jul. 01, 2026
Debt instrument, convertible, conversion rate	85.1064
Debt instrument, face amount	$ 1,000
Debt instrument, convertible, conversion price	$ 11.75
Debt instrument, conversion description	SEACOR Marine has the right to cause the mandatory conversion of the New Convertibles Notes into Common Stock if the daily VWAP of the Common Stock equals or exceeds (A) in the case of New Convertible Notes held by affiliates of Carlyle, 150% of the Conversion Price and (B) in the case of New Convertible Notes held by any Person other than Carlyle, 115% of the Conversion Price, in each case for each of the 20 consecutive trading days.
Debt instrument, percentage of new convertible notes to be purchased	100.00%
Debt instrument, percentage of new convertible notes to be redeemed	100.00%
Old Convertible Notes \| Subsequent Event \| Carlyle
Debt Instrument [Line Items]
Debt instrument, conversion price percentage	150.00%
Old Convertible Notes \| Subsequent Event \| Other Than Carlyle
Debt Instrument [Line Items]
Debt instrument, conversion price percentage	115.00%
SEACOR Marine Foreign Holdings Credit Facility
Debt Instrument [Line Items]
Prepayment of credit facility		$ 5,300,000
Line of credit facility, outstanding amount		$ 74,700,000
Cash and Cash Equivalents, Percentage					35.00%	35.00%
SEACOR Marine Foreign Holdings Credit Facility \| Forecast
Debt Instrument [Line Items]
Cash and Cash Equivalents, Percentage				35.00%
SEACOR Marine Foreign Holdings Credit Facility \| Tranche A
Debt Instrument [Line Items]
Maturity date		Sep. 30, 2023
Loan principal amount		$ 19,800,000
SEACOR Marine Foreign Holdings Credit Facility \| Tranche B
Debt Instrument [Line Items]
Loan principal amount		$ 54,900,000
SEACOR Marine Foreign Holdings Credit Facility \| SOFR \| Tranche B
Debt Instrument [Line Items]
Maturity date		Sep. 30, 2023
Margin percentage		4.75%
Debt Instrument, extended maturity date		Mar. 31, 2026
SEACOR 88/888 Term Loan
Debt Instrument [Line Items]
Long-term debt			$ 5,500,000
Percentage of debt obligations outstanding			50.00%
Minimum \| Senior PIK Toggle Notes due 2026 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument percentage	8.00%
Minimum \| Guaranteed Notes \| Subsequent Event
Debt Instrument [Line Items]
Notes redeemable denomination amount	$ 10,000,000.0
Minimum \| SEACOR Marine Foreign Holdings Credit Facility
Debt Instrument [Line Items]
Cash and Cash Equivalents, Percentage							7.50%
Cash and Cash Equivalents					$ 35,000,000.0		$ 35,000,000.0
Minimum \| SEACOR Marine Foreign Holdings Credit Facility \| Tranche A
Debt Instrument [Line Items]
Margin percentage		3.75%
Minimum \| SEACOR 88/888 Term Loan \| SOFR
Debt Instrument [Line Items]
Interest rate margin			3.75%
Maximum \| Senior PIK Toggle Notes due 2026 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument percentage	9.50%
Maximum \| SEACOR Marine Foreign Holdings Credit Facility \| Tranche A
Debt Instrument [Line Items]
Margin percentage								4.75%
Maximum \| SEACOR 88/888 Term Loan \| SOFR
Debt Instrument [Line Items]
Interest rate margin			4.75%