Derivatives notional amount.

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- Definition

Proceeds to be received from sale of business.

+ References

No definition available.

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
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- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ References

No definition available.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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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

The number of derivative instruments of a particular group held by the entity.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Instruments and Hedging Strategies - Additional Information (Details) $ in Thousands, £ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2021 GBP (£)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jul. 23, 2021	Jun. 01, 2021	Dec. 20, 2018
Derivative [Line Items]
Derivative gains (losses) on cash flow hedges	$ 219		$ (2,139)	$ (1,901)
Equity method investment, ownership percentage					50.00%	50.00%	49.00%
Estimated fair value of derivative instruments from continuing operations	1,800
Credit risk adjustment	200
Interest Rate Swap
Derivative [Line Items]
Derivative gains (losses) on cash flow hedges	$ 219		$ (2,139)	(1,901)
Forward Exchange Contract \| Windcat Workboats Holdings Ltd
Derivative [Line Items]
Proceeds to be received from sale of business \| £		£ 31.5
Maximum
Derivative [Line Items]
Equity method investment, ownership percentage	50.00%		50.00%
Minimum [Member]
Derivative [Line Items]
Equity method investment, ownership percentage	20.00%
Minimum [Member] \| SEACOR Marine Foreign Holdings
Derivative [Line Items]
Equity method investment, ownership percentage	50.00%
Cash Flow Hedging
Derivative [Line Items]
Derivative gains (losses) on cash flow hedges	$ 2,300		$ (700)	$ (1,300)
Cash Flow Hedging \| 3.32% Interest Rate Swap Agreement \| Designated as Hedging Instrument \| SEACOR Marine Foreign Holdings
Derivative [Line Items]
Derivative, fixed interest rate	3.32%
Derivative, notional amount	$ 6,800
Cash Flow Hedging \| 3.195% Interest Rate Swap Agreement \| Designated as Hedging Instrument \| SEACOR Marine Foreign Holdings
Derivative [Line Items]
Derivative, fixed interest rate	3.195%
Derivative, notional amount	$ 37,500
Cash Flow Hedging \| Interest Rate Swap \| Designated as Hedging Instrument \| SEACOR 88/888
Derivative [Line Items]
Derivative, fixed interest rate	3.175%
Derivative, notional amount	$ 5,500
Cash Flow Hedging \| Interest Rate Swap \| Designated as Hedging Instrument \| MexMar
Derivative [Line Items]
Equity method investment, ownership percentage	49.00%
Derivative, notional amount	$ 58,100
Derivative, number of instruments held, total	5
Cash Flow Hedging \| Maximum \| Interest Rate Swap \| Designated as Hedging Instrument \| MexMar
Derivative [Line Items]
Derivative, fixed interest rate	2.10%
Cash Flow Hedging \| Minimum [Member] \| Interest Rate Swap \| Designated as Hedging Instrument \| MexMar
Derivative [Line Items]
Derivative, fixed interest rate	1.71%
Derivative Liabilities \| Fair Value Hedging
Derivative [Line Items]
Recognized gain (loss) on hedged item in fair value hedge	$ 400		$ (900)