Cost associated with debt modification.

No definition available.

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- Definition

Debt instrument maturity year.

+ References

No definition available.

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- Definition

Percentage of proceeds from asset sales, net of commission paid.

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No definition available.

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- Definition

Premium paid on debt repurchase.

+ References

No definition available.

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- Definition

Discussion of whether the debt instrument is secured or unsecured, and, if secured, a description of the collateral and guarantees required or provided.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

+ References

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Discussion of the facts and amounts pertaining to each failure to comply with an affirmative or negative covenant of a long-term debt instrument, including violating payment terms or an inability to meet certain minimum financial requirements or achieve or maintain certain financial ratios. The discussion would generally be expected to also include whether or not the failure can and will be overcome and a description of the terms of any waivers, including the amount of the waiver and the period of time covered by the waiver, and if reclassification of long-term debt to current has been made in the current balance sheet.

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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

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

+ References

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Indebtedness - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended		12 Months Ended
	Jul. 31, 2017	Nov. 30, 2019	Jul. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019	Mar. 01, 2018	Feb. 01, 2018
Debt Instrument [Line Items]
Restricted cash				$ 5,755	$ 25,953
Loss on early extinguishment of debt					(8,119)
GulfMark \| Term Loan Facility
Debt Instrument [Line Items]
Repayment of outstanding debt					100,000
Loss on early extinguishment of debt					8,100
Borrowing capacity terminated amount					25,000
Offer
Debt Instrument [Line Items]
Face value of repurchased notes		$ 125,000
Premium paid		8.50%
Total repurchase price		$ 135,600
Debt modification/deferred premium and other costs		$ 11,400
Offer \| Senior Notes \| Maximum
Debt Instrument [Line Items]
Aggregate principal amount					$ 25,400			$ 24,700
8.00% New Secured Notes Due August 2022
Debt Instrument [Line Items]
Debt instrument interest rate				8.00%
Aggregate principal amount	$ 350,000		$ 350,000	$ 350,000		$ 100	$ 40
Debt instrument maturity year			2022	2022
8.00% New Secured Notes Due August 2022 \| Offer
Debt Instrument [Line Items]
Percentage of proceeds from Asset Sales, net of commission paid	65.00%
8.00% New Secured Notes Due August 2022 \| Level 2
Debt Instrument [Line Items]
Fair value of debt outstanding				$ 237,600
8.00% New Secured Notes Due August 2022 \| Plan of Reorganization
Debt Instrument [Line Items]
Debt instrument maturity date				Aug. 01, 2022
Debt instrument interest term				Interest on the Secured Notes accrues at a rate of 8.00% per annum and are payable quarterly in arrears on February 1, May 1, August 1, and November 1 of each year in cash.
Debt instrument frequency of periodic payment of interest				quarterly
Debt Instrument default description				The Secured Notes have a quarterly minimum trailing year interest coverage requirement that began June 30, 2019. Minimum liquidity requirements and other covenants are set forth in the Indenture and are in effect from July 31, 2017. The Indenture also contains certain customary events of default and has a make-whole provision.
Debt instrument collateral description				Until terminated under the circumstances described in this paragraph, the Secured Notes and the guarantees by the Guarantors are secured by the Collateral (as defined in the Indenture) pursuant to the terms of the Indenture and the related security documents. The Trustee’s liens upon the Collateral and the right of the holders of the Secured Notes to the benefits and proceeds of the Trustee’s liens on the Collateral will terminate and be discharged in certain circumstances described in the Indenture, including: (i) upon satisfaction and discharge of the Indenture in accordance with the terms thereof; or (ii) as to any of our Collateral or the Guarantors that is sold, transferred or otherwise disposed of by us or the Guarantors in a transaction or other circumstance that complies with the terms of the Indenture, at the time of such sale, transfer or other disposition.