Guarantee Fee Income, Interest Rate Earned On Outstanding Guarantees

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- Definition

Repayments of Long-term Debt and Payments for Conversion Option in Convertible Debt

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- Definition

Securities Repurchase Plan, Remaining Authorized Repurchase Amount

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

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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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Long-Term Debt (Details) - USD ($)		3 Months Ended		9 Months Ended
Long-Term Debt (Details) - USD ($)	Sep. 14, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Common stock, par value (in dollars per share)		$ 0.01		$ 0.01
Securities Repurchase Plan, Remaining Authorized Repurchase Amount		$ 102,200,000		$ 102,200,000
Debt extinguishment gains (losses), net		(254,000)	$ (777,000)	1,348,000	$ (2,073,000)
Repayments of long-term debt				69,048,000	$ 66,685,000
Letters of credit outstanding, amount		1,100,000		$ 1,100,000
Interest rate earned on guarantees				0.50%
SEACOR Marine Holdings Inc.
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure, undiscounted		$ 10,400,000		$ 10,400,000
Three Point Zero Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		3.00%		3.00%
Two Point Five Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.50%		2.50%
Three Point Two Five Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		3.25%		3.25%
Convertible Debt \| Three Point Zero Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		3.00%		3.00%
Debt instrument, repurchased face amount	$ 34,500,000	$ 15,600,000		$ 15,600,000
Repayments of Long-term Debt and Payments for Conversion Option in Convertible Debt				15,400,000
Debt Instrument, Redemption Price, Percentage	100.00%
Debt extinguishment gains (losses), net				$ (600,000)
Convertible Debt \| Two Point Five Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.50%		2.50%
Debt instrument, repurchased face amount		$ 12,900,000		$ 12,900,000
Repayments of Long-term Debt and Payments for Conversion Option in Convertible Debt				10,900,000
Debt extinguishment gains (losses), net				1,900,000
Long-term Debt, Gross		$ 51,600,000		$ 51,600,000
Convertible Debt \| Three Point Two Five Percentage Convertible Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		3.25%		3.25%
Line of Credit \| Revolving Credit Facility \| SEACOR Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity		$ 125,000,000.0		$ 125,000,000.0
Line of Credit \| Revolving Credit Facility \| SEA-Vista 2019 Credit Facility
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity		$ 100,000,000.0		100,000,000.0
Line of Credit \| Secured Debt \| SEA-Vista 2019 Credit Facility, Term Loan
Debt Instrument [Line Items]
Repayments of long-term debt				7,500,000
Notes Payable, Other Payables
Debt Instrument [Line Items]
Repayments of long-term debt				$ 700,000