Debt instrument maturity year.

No definition available.

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- Definition

Debt repayment utilization of cash in hand.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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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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- Definition

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

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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- 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

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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- Definition

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 ($)		1 Months Ended	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2017	Dec. 31, 2018	Jan. 01, 2019	Mar. 01, 2018	Feb. 01, 2018	Dec. 31, 2017
Debt [Line Items]
Restricted cash			$ 25,953,000				$ 21,300,000
Cash from acquisition used for repayment of debt			43,806,000
Loss on early extinguishment of debt			(8,119,000)
GulfMark \| Term Loan Facility
Debt [Line Items]
Cash from acquisition used for repayment of debt			37,700,000
Cash on hand used for repayment of debt			72,000,000
Repayment of outstanding debt			100,000,000
Loss on early extinguishment of debt			8,100,000
Borrowing capacity terminated amount			25,000,000
Offer \| Senior Notes \| Maximum
Debt [Line Items]
Aggregate principal amount			$ 25,400,000			$ 24,700,000
8.00% New Secured Notes Due August 2022
Debt [Line Items]
Debt instrument interest rate			8.00%
Aggregate principal amount	$ 350,000,000	$ 350,000,000	$ 350,000,000
Debt instrument maturity year		2022	2022
8.00% New Secured Notes Due August 2022 \| Offer
Debt [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 [Line Items]
Fair value of debt outstanding			$ 359,400,000
8.00% New Secured Notes Due August 2022 \| Plan of Reorganization
Debt [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, beginning November 1, 2017.
Debt instrument frequency of periodic payment of interest			quarterly
Debt Instrument default description			The Secured Notes have quarterly minimum trailing twelve months interest coverage requirement that begins 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 a make-whole provision.
Debt instrument collateral description			the Secured Notes and the guarantees by the Guarantors will be 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.
Tendered Notes
Debt [Line Items]
Aggregate principal amount					$ 46,023
Tendered Notes \| Subsequent Event
Debt [Line Items]
Aggregate principal amount				$ 160,000