The additional interest percentages increases required for overdue or defaulted amounts.

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The amount of accrued interest on outstanding debt that is subject to compromise.

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The principal amount of outstanding debt that is subject to compromise.

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Additional borrowing capacity under the credit facility with consideration of current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The minimum percentage of outstanding long-term debt that is entered into a forbearance agreement in order to delay the occurrence of foreclosure.

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The percentage of outstanding principle for long-term debt entered into a restructuring support agreement.

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Redemption price on the principal amount , stated in percentage.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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

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

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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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Amount, after accumulated amortization, of debt premium.

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Weighted average interest rate of debt outstanding.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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No definition available.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Total amount of liabilities subject to compromise.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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No definition available.

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Note 5 - Debt (Details Textual)	3 Months Ended	6 Months Ended	12 Months Ended				24 Months Ended
Note 5 - Debt (Details Textual)	Mar. 31, 2016 USD ($)	Jun. 30, 2017 NOK	Mar. 14, 2020	Mar. 14, 2019	Mar. 14, 2018	Dec. 31, 2016 USD ($)	Mar. 12, 2022	Jun. 30, 2017 USD ($)	May 18, 2017 USD ($)	May 17, 2017	May 15, 2017	Apr. 14, 2017	Mar. 31, 2017 USD ($)	Mar. 08, 2017 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2012 USD ($)	Dec. 27, 2012 NOK
Long-term Debt, Gross						$ 489,797,000		$ 134,156,000
Liabilities Subject to Compromise								448,124,000
Debt Issuance Costs, Net						6,894,000
Debt Instrument, Unamortized Premium						423,000
Multicurrency Credit Facility [Member]
Long-term Debt, Gross						49,000,000		$ 72,000,000
Additional Interest Percentage Increase for Overdue or Defaulted Amounts		2.00%
Multicurrency Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		2.75%
Multicurrency Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate		4.00%
Multicurrency Credit Facility [Member]
Line of Credit Facility, Number of Vessels Securing the Facility		24,000,000						24,000,000
Long-term Line of Credit								$ 72,000,000
Long-term Debt, Weighted Average Interest Rate, at Point in Time		5.13%						5.13%
Line of Credit Facility, Maximum Borrowing Capacity								$ 100,000,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		1.25%
Line of Credit Facility, Additional Borrowing Capacity														$ 10,000,000
Debt Issuance Costs, Net													$ 2,300,000
Multicurrency Credit Facility [Member] \| Swingline Loans [Member]
Line of Credit Facility, Maximum Borrowing Capacity								25,000,000
Multicurrency Credit Facility [Member] \| Letter of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity								5,000,000
Norwegian Facility [Member]
Long-term Line of Credit								62,200,000
Line of Credit Facility, Maximum Borrowing Capacity								55,000,000
Debt Instrument, Face Amount		NOK 210,000,000						$ 25,600,000									NOK 600,000,000
Additional Interest Percentage Increase for Overdue or Defaulted Amounts		2.00%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		5.00%
Debt, Weighted Average Interest Rate		5.86%						5.86%
Debt Issuance Costs, Net													1,100,000
Norwegian Facility [Member] \| GulfMark Rederi AS [Member]
Line of Credit Facility, Maximum Borrowing Capacity									$ 35,000,000
Norwegian Facility [Member] \| GulfMark UK [Member]
Line of Credit Facility, Number of Vessels Securing the Facility		16						16
Norwegian Facility [Member] \| GulfMark Rederi AS [Member]
Line of Credit Facility, Number of Vessels Securing the Facility		6						6
Norwegian Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		8.00%
Senior Notes [Member]
Interest Payable								$ 13,700,000
Long-term Debt, Forbearance Agreement, Minimum Percentage of Outstanding Debt												50.00%
Liabilities Subject to Compromise, Accrued Interest								18,500,000
Liabilities Subject to Compromise, Debt								429,600,000
Senior Note Due 2022 [Member]
Long-term Debt, Gross	$ 479,000,000					429,640,000									$ 499,000,000
Debt Instrument, Face Amount																$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage																6.375%
Debt Issuance Costs, Gross													12,700,000
Debt Issuance Costs, Net													6,700,000
Debt Instrument, Unamortized Premium													$ 400,000
Debt Instrument, Repurchased Face Amount	20,000,000					69,400,000									$ 1,000,000
Gain (Loss) on Repurchase of Debt Instrument	$ 10,100,000					$ 35,900,000
Senior Note Due 2022 [Member] \| Scenario, Forecast [Member]
Redemption Price as Percentage of Principal Amount Premium and Interest			101.063%	102.125%	103.188%		100.00%
Unsecured Senior Notes [Member]
Long-term Debt, Restructuring Support Agreement, Percentage of Aggregate Outstanding Principle										50.00%	50.00%
Debt Instrument, Interest Rate, Stated Percentage											6.375%