Note 2 - Bankruptcy and Related Matters (Details Textual)		3 Months Ended
	May 15, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 NOK	Jun. 30, 2017 USD ($)	May 18, 2017 USD ($)	May 17, 2017	Dec. 31, 2016 USD ($)	Dec. 27, 2012 NOK
Rights Offering Arrangement, Value	$ 125,000,000
Rights Offering, Percentage of Common Stock Available for Purchase	60.00%
Rights Offering, Backstopped Commitment Premiums Paid, Percent	6.00%
Rights Offering, Reorganized Equity Used for Commitment Premium, Percent	3.60%
Reorganized Equity, Aggregate Equity Issued to Noteholders, Percent	35.65%
Maximum Aggregate Ownership Percentage of Common Stock to Non-U.S. Citizens	25.00%
Reorganized Equity, Pro Rata Per Share, Percent	0.75%
Reorganized Equity, Pro Rata Warrants Per Share, Percent	7.50%
Reorganized Equity, Warrant Term	7 years
Reorganized Equity, Equity Used in Computation of Exercise Price	$ 1,000,000,000
Backstop Commitment Agreement, Commitment Premium	7,500,000
Backstop Commitment Agreement, Termination Fee	$ 7,500,000
Debtor-in-Possession Financing, Amount Arranged					$ 35,000,000
Debtor-in-Possession Financing, Equity Interest Pledged as Security					65.00%
Liabilities Subject to Compromise				$ 448,124,000
Debtor Reorganization Items, Legal and Advisory Professional Fees		$ 5,100,000
Norwegian Facility [Member]
Debt Instrument, Face Amount			NOK 210,000,000	25,600,000				NOK 600,000,000
Line of Credit Facility, Maximum Borrowing Capacity				55,000,000
Norwegian Facility [Member] | GulfMark Rederi AS [Member]
Line of Credit Facility, Maximum Borrowing Capacity					$ 35,000,000
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%
Senior Notes [Member]
Liabilities Subject to Compromise, Debt				429,600,000
Liabilities Subject to Compromise, Accrued Interest				$ 18,500,000